The attackers who shot and killed a U.S. paratrooper in eastern Afghanistan over the weekend later fired rockets at an American base in the same area, the military said Monday.

The rocket attack, which caused no casualties, followed a gunbattle Saturday near Shkhin that killed one enemy fighter, wounded another and left U.S. 82nd Airborne Division paratrooper Sgt. Steven Checo dead, the U.S. military statement said.

Elsewhere, a spokesman said a weekend helicopter crash that killed seven German peacekeepers was likely caused by a mechanical failure.

"We believe it was a technical problem. There are no indications yet that it was anything else," said Lt. Col. Paul Weber, a spokesman for the German peacekeeping contingent in Kabul.

The Sikorsky CH53 chopper crashed Saturday near Kabul airport. Weber said the bodies of all seven peacekeepers would be returned to Germany by Christmas.

Some 4,800 peacekeeping force are deployed in the capital city. About 8,000 American troops are deployed across the mountainous central Asian nation, most along the eastern border with Pakistan.

Steven Checo, of New Jersey, was the first U.S. soldier killed in combat in Afghanistan since August, when a soldier died of wounds suffered in a July ambush.

After the Shkhin skirmish, the group of seven to nine attackers carrying AK-47 assault rifles and other military equipment fled across the border into Pakistan, the U.S. military said.

U.S. Special Forces troops, who were conducting an investigation of the incident in the same area, said the same group fired six rockets at the U.S. base in Shkhin several hours later. Six alarm clocks -- apparently timing devices -- were found nearby, the statement said.

Rockets, many Chinese-made and connected to crude timers, have been fired frequently at U.S. troops stationed at the Khost airfield in eastern Afghanistan. The rockets, sometimes leaned against rocks, are difficult to aim and have rarely caused casualties.

In the most recent incident, a rocket hit near the Jalalabad airport, missing an Afghan army garrison and causing no injuries, police said.

The attack occurred one day after the Afghan authorities in Jalalabad seized scores of other rockets destined for Taliban and Al Qaeda fugitives. No arrests were made in the seizure near the eastern border with Pakistan.