Followers of terrorist Abu Musab al-Zarqawi (search) would attack the White House or the Vatican if their leader chooses to target those sites, the Al Qaeda (search) in Iraq's deputy chief purportedly said in an Internet statement posted Monday.

The written statement, signed in the name of Abu Abdel-Rahman al-Iraqi, also threatened to attack Iraqi security forces and officials, including incoming Prime Minister Ibrahim al-Jaafari (search), a Shiite Muslim.

"We are after you as long as we are alive," the statement said of al-Jaafari.

The authenticity of the statement, which appeared on an Internet site known for carrying extremist Islamic material, could not be verified.

The statement appeared to be the first attributed to al-Iraqi, whose name had not previously surfaced as al-Zarqawi's deputy.

"We have taken our decision, depending on God, to fight the infidels, the hypocrites and the villains," the statement said. "Even if you (al-Zarqawi) take us to the White House and the bastion of the Vatican, we will stick close to you until you achieve your aim."

Al-Iraqi vowed to fight Iraqi police and national guard units, whom he described as "the tail of the crusaders ... the paws of the Americans and the evil Rafidah (Shiites) and we will show no mercy toward you."

Al-Zarqawi's group, believed to be comprised mainly of Sunni Muslim extremists, has claimed responsibility for carrying out the deadliest attacks on U.S. troops, Iraqi security forces and government officials.