Once everything was ready, the cleanup operation began.
At the Block B command center in the industrial park, Calista stood before the huge map in the middle of the room.
On the map, Block D had been divided into six sectors, labeled A, B, C, D, E, and F.
Inside each sector, colored pushpins of different colors and sizes marked the estimated walker distribution, key buildings, preset clearance routes, and blocking points.
Along the edge of the map, a row of small screens showed real-time wide-angle footage transmitted by drones hovering at safe high-altitude positions far from the interference zone, as well as the communication status lights for each squad's encrypted channel.
Leah was stationed at the Rock Fortress command center, responsible for overall defense coordination and reserve deployment.
At the frontline command post here, Calista personally held command, while Maya and Lieutenant Welles served as the forward commander and deputy commander.
At that moment, both of them had already taken position at the forward command points established along the edge of Block D.
The force participating in the cleanup operation was both a concentrated display of Rock Fortress's defensive strength and a risky test by fire.
The core force consisted of thirty-six experienced official members of the Defense Force. They had been split up and assigned to the various reserve squads as squad leaders.
Their task was to provide critical fire support, steady the line, and make the right tactical decisions at dangerous moments.
The remaining thirty-odd official Defense Force members were simultaneously responsible for patrol and defense at Rock Fortress, Blackberry Ranch, and the industrial park's A, B, and C areas, preventing the rear from being left exposed.
The main force this time consisted of more than one hundred and twenty Defense Force reservists.
They were the "new blood" selected from ordinary survivors over the past winter, put through strict basic training, and sent several times to participate in clearing scattered walkers around the base.
The reservists were organized into twelve ten-person squads, each led by three veteran Defense Force members.
This was the first time the reservists had faced a human-versus-walker battle on such a scale.
In addition, there was a twenty-person engineering support team responsible for breaching doors, setting up roadblocks, and conducting preliminary assessments of equipment, as well as a fifteen-person mobile medical team that had established a temporary field aid station behind the forward command point.
"All units, final communications check," Calista ordered over the encrypted channel.
Maya reported, "Sector A, First and Second Reserve Squads in position, led by veterans. Communications clear.
Sector B, Third and Fourth Squads in position. Passage cleared, awaiting orders.
Sectors C, D, E, and F, all squads have reached their attack launch positions. Communications normal."
Bossie said, "Drone report. Visible walker groups along the outskirts of Block D are moving strangely. They seem to have been disturbed by our assembly and are slowly gathering toward the main entrances. Numbers are increasing."
"Forward medical station ready."
"Engineering team standing by."
The area of Block D circled in red was like a sleeping beast slowly being awakened.
The estimated two thousand walkers were only the visible portion. How many more were hidden deep inside those silent factories, warehouses, and office buildings?
"Proceed according to plan. All sectors advance simultaneously," Calista gave the final order. "Maintain formation. Use alternating fire support. Prioritize clearing open areas and roads.
Before entering any building, conduct thorough reconnaissance and lure the walkers out. Veteran members control the pace. Reservists follow orders strictly.
Medics and engineering teams are to maintain a following distance of at least two hundred meters."
"Copy!"
The instant Maya and Lieutenant Welles issued their orders, combat erupted across multiple sectors at once.
Sector A was the first to engage. It had a main road connecting Block D to the outside, with relatively open loading zones and parking lots on both sides.
The drone feed showed more than a hundred walkers pouring out from side roads and behind factory buildings, dragging their rotten bodies as they staggered toward the defensive line established by the First and Second Squads.
"Everyone, hold steady! Front row, shields up! Rear row, fire at will. Aim for the head, and don't waste ammo!" the veteran team leader at the front roared.
The front-line members immediately raised reinforced metal shields or thick wooden boards, leaning slightly forward with their feet planted firmly on the ground.
The members in the rear extended their gun barrels through the gaps between shields or from the flanks.
"Fire!"
"Bang! Bang! Bang!"
Some used rifles, others submachine guns, but all of them were fitted with suppressors. A barrage of muffled shots burst out from every direction like firecrackers.
The walkers at the front fell as if cut down by an invisible scythe. Their rotting bodies burst apart in patches under the rain of bullets, then collapsed to the ground, releasing a thick, nauseating stench.
But there were too many walkers, and they knew no fear. They did not know how to retreat.
Often, the moment the ones in front fell, the ones behind stepped over their remains and kept coming.
Bullets to the torso could only make the walkers stagger. Unless their heads were destroyed with precision or their spines were completely severed, they would keep crawling toward them, even dragging half-ruined bodies behind them.
That was one of the most disgusting things about walkers.
"Reloading!"
"Gap on the left! Fill it!"
One reservist was so nervous that his hands shook while reloading, and his magazine dropped to the ground. He hurriedly crouched to pick it up.
A half-mangled walker suddenly lunged into the gap in the shields, right up in his face. If the long wooden board had not blocked it, its reeking pus would have splattered straight into his mouth.
The team member cried out in fright and nearly dropped the magazine again.
"Duck!" someone beside him snapped.
A heavy fire axe came chopping down through the gap with a rush of wind, slamming hard into the walker's temple. Filthy blood and brain matter splattered across the ground.
The veteran leading the team did not even look at the stunned reservist. "Pick up the magazine! Keep fighting! You idiot, do you want to die?"
The main battlefield in Sector B was a narrow passage piled with abandoned shipping containers.
Visibility was limited there, and walkers kept emerging from the gaps between containers and from the tops of them.
In Third Squad, Leo gripped a shotgun tightly and held a vulnerable corner on the team's flank.
"Watch overhead!" he shouted hoarsely, raising his gun and blasting apart a walker that had leaped down from the top of a container.
Foul chunks of flesh and slime splattered all over Leo, but he did not even blink as he quickly ejected the shell and chambered another.
Suddenly, he heard his teammate Brenda scream behind him.
He turned and saw Brenda knocked down by a walker that had rushed out from a blind spot. Her rifle had slipped from her hands, and the walker was opening its rotten mouth to bite down.
Leo's head buzzed. Acting on instinct, he took two steps forward, shoved the scorching barrel of his shotgun into the walker's gaping mouth, and pulled the trigger hard.
"Boom!"
The back of the walker's head blew apart, along with a small section of the container wall behind it.
Brenda lay on the ground, her face splattered with foul blood and shredded flesh, still badly shaken.
Leo grabbed her and hauled her up, shoved her back into formation, and roared hoarsely, "Damn it, Brenda, don't freeze up! Keep shooting!"
On the command center's drone screens and communication channels, chaotic and fierce fighting was breaking out everywhere.
"Sector A, frontal pressure is too heavy! Request permission to use preset Molotov cocktails to slow them down!"
"Permission granted. Watch the wind direction. Keep clear of our people and the buildings."
"Sector B clearance progress at thirty-five percent. No casualties."
"Sector C reporting. Dense impact sounds coming from inside Warehouse Two. Suspected large number of trapped walkers. Setting up audio decoys now."
"Sector D, Eighth Squad pushed too far ahead and has separated from Seventh Squad. They're partially surrounded by a walker horde and holding position for rescue!"
"What?" Calista's eyes sharpened. "Maya, what happened?"