It was a means to an end, collateral damage in a carefully orchestrated terrorist assault on a far more dazzling prize: the elite citadel of an American-built university in Kabul that trains some of Afghanistan's most ambitious and promising students.

But the small, low-budget government school for the blind, a collection of sheds and low-slung classrooms located just across a low, cinder-block wall from the modern multistory buildings of the American University of Afghanistan, was the suicide attackers' steppingstone to paradise.

About 7 p.m. Wednesday, a truck crashed through the blue metal gate of the modest institution, whose misspelled sign reads "Visually Impaired High School and Vacational School." The driver roared across the dusty parking lot, screeched to a halt in the yard and detonated a cargo of explosives. The impact instantly toppled the wall just a few feet away, allowing a squad of gunmen to pour through it and into the university compound.

Once inside, they wreaked havoc for nine hours while students cowered in their classrooms, before the gunmen were killed by Afghan security forces. At least 16 people died and 53 others were injured, health officials said. Across the road, a much larger university compound, surrounded by high walls and guard towers, was unscathed. The attackers, whose affiliation is not yet known, had picked the most vulnerable spot to breach.

On Thursday, the school for the visually impaired was empty. Its classrooms were full of debris, the roofs had collapsed, and a metal shed used as a clinic was burned and twisted from the explosion. The charred remains of the truck sat in the grassy yard. Across the wall, university workmen dug through rubble, amid shreds of barbed wire coils, and carried it away.

"This is a big blow for the university students and lecturers who were working for a bright future for Afghanistan, but it has done enormous damage to our school, too," said Humayun Azizi, 30, a blind teacher there who was being led through the debris-strewn yard by a boy. He said one night guard at the school was killed by the blast.

"We were lucky the students had already left for the day, but it will take a long time for us to reopen," Azizi said, putting his hand on the boy's shoulder as the pair walked away. The day school, which is run by the Afghan government with support from the World Bank, teaches basic academic skills and trades to 300 students with limited or no vision.

Outside, on the main road, there was nothing but a thick, black residue of swerving tire treads, leading straight through the blue metal gate, to indicate that this had been the terrorists' first stop on their mission to target a high-profile symbol of Western education and what they perceive as its evils.

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