BAGHDAD, Iraq, (AP) - Two key members of radical anti-American Shiite cleric Muqtada al-Sadr's political and military organization were gunned down just days before the U.S. and Iraqi forces planned to open a massive security drive in Baghdad.

Ali Khazim, who ran al-Sadr's political organization in volatile Diyala province northeast of Baghdad, was killed Sunday by U.S. forces at his home in Howaider village, 12 miles east of Baqouba, Saleh al-Ageili, a spokesman for the Sadr Movement's parliamentary bloc, said on Monday. Provincial police confirmed al-Ageili's account.

"What has happened to Khazim is part of the series of provocative acts by the occupation forces against the Sadr movement. The occupation forces know well who are the terrorists and their whereabouts, yet they are targeting our people," al-Ageili told The Associated Press.

The U.S. military did not immediately respond to telephone and e-mail requests for comment.

The second official, Khalil al-Maliki, a key figure in al-Sadr's Mahdi Army militia in Basra, was killed by three gunmen in a drive-by shooting on Sunday in the southern city of Basra, police reported. He survived an assassination attempt in the city last year.

As many as seven key figures in the al-Sadr organization have been killed or captured in the past two months, at least three of them by U.S. forces, after Prime Minister Nouri al-Maliki, also a Shiite, dropped his protection for the organization — a crucial backer in his rise to power.

The coming security drive, to which President Bush has dispatched 21,500 additional American forces, was seen as a last-chance effort to quell the sectarian violence ravaging the capital and surrounding regions.