A rocket slammed into a street outside an apartment building in the Afghan capital Monday, killing a man and wounding five other people including a small boy, officials said.

The missile struck outside a residential building complex in eastern Kabul, said Gen. Ali Shah Paktiawal, the city's police director of criminal investigation.

One young boy was seriously wounded and taken to a hospital, said a local police chief, Hasib Arian.

A resident of the building, who identified himself only as Maliyar, said his 27-year-old neighbor died later at the hospital.

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Insurgent violence in Afghanistan has escalated in recent months after a winter lull, especially in the volatile south and east, but Kabul has also seen a rise in attacks this spring.

Separately, an Afghan soldier shot and killed two U.S. troops Sunday outside a top-security prison being revamped to house Afghans transferred from the Guantanamo Bay detention camp, a U.S. military spokesman said.

Other Afghan troops fatally shot the gunman at Pul-e-Charkhi prison, about 20 miles east of Kabul, said Maj. Sheldon Smith, a spokesman for Combined Security Transition Command, which trains Afghan security forces. The shooter also wounded two U.S. soldiers.

The Americans were working as mentors to Afghan troops providing external security for the prison, Smith said. U.S. and Afghan authorities were trying to determine the motive for the attack, he said.

"All indications are" that the shooter was a member of the Afghan National Army, the post-Taliban force trained mainly by the American military, Smith said.

He said the U.S. soldiers were in two vehicles when they were shot. The victims were not identified, and Smith provided no further details of the incident.

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