Three rockets were fired toward Kabul early Tuesday, but they struck far from the site where Afghans were holding their historic constitutional council. There were no casualties.

The blasts came amid tight security in the capital, with 500 delegates here for a loya jirga (search), or grand council, to ratify Afghanistan's first post-Taliban constitution.

The target of the rockets was not clear, but the U.S. military has warned that Taliban (search) insurgents might try to strike the council. Leaflets denouncing the gathering have been appearing in several towns.

The rockets detonated at about 12:50 a.m. some 6 miles north of the council site, causing no casualties but damaging a mud house, Afghan and international security officials said.

Troops from the international peacekeeping force that patrols Kabul clambered onto the punctured roof of the house, gathered shards of metal from the rocket and cordoned off the area for investigation.

Another rocket hit a field, and the third failed to explode, said Rahmatullah, a Kabul district police commander who like many Afghans uses only one name.

None of the rockets hit peacekeeping installations, the force said in a statement.

Thousands of Afghan troops, as well as the 5,500-strong NATO-led peacekeeping force, have been providing security for the loya jirga, checking most cars on major streets. Peacekeepers and Afghan intelligence units have been patrolling in hills surrounding the city to prevent any rocket attacks.

A missile was fired Saturday toward the peacekeepers' headquarters but fell well short. The last rocket attack in the capital was on Dec. 4, when a rocket landed in a field next to the U.S. Embassy less than two hours after Defense Secretary Donald H. Rumsfeld (search) left the city.