The United States has captured the alleged mastermind of Bali bombings, in which more than 180 people died, and the recent J W Marriott blast in Jakarta that killed 13.

The capture of Jemaah Islamiyah chief Riduan Isamabudian, also known as Hambali, is said to be the biggest catch for the US after the September 11, 2001.

"His capture is another important victory in the global war on terrorism and a significant blow to the enemy," White House spokesperson Scott McClellan said.

Another country had helped the US capture him, CNN said, adding he was a senior Al Qeada member and the most wanted man in Asia.

There might be procedural wrangles, as both Indonesia and the United States would want Hambali to stand trial on their soil.

According to CNN, President George W Bush was informed about the arrest on Wednesday night.