U.N. weapons inspectors say they plan to get tougher with Iraq in their hunt for weapons of mass destruction. On Wednesday, they visited one of Saddam Hussein's main presidential palaces.

For the second time since resuming inspections November 27 the U.N. weapons team visited one of Saddam Hussein's eight presidential palaces.

For more than four hours Wednesday, inspectors investigated what is popularly known as the Old Palace. Located in the heart of Baghdad overlooking the Tigris River, the palace was built in the late 1950s and was bombed several times during the 1991 Gulf war. The palace has since been rebuilt and is considered Saddam Hussein's main office and also houses the offices of Iraq's Special Security Forces and Republican Guard.

An Iraqi information ministry official described the palace as a sensitive site.

On December 3, weapons inspectors made their first visit to a presidential palace in Iraq. Although that search was conducted quickly, it prompted protests from Iraqi officials who said it had nothing to do with the search for weapons of mass destruction.

Iraqis have recently complained that U.N. inspectors have detained employees at inspection sites and have repeatedly violated traffic rules while traveling to suspected weapons sites. They also charge that the inspectors have been asking questions that have nothing to do with searching for banned weapons.

On Sunday, chief U.N. weapons inspector Hans Blix and the head of the International Atomic Energy Agency, Mohamed ElBaradei are due to arrive in Baghdad for talks with Iraqi officials.

Mr. Blix said Wednesday the inspectors planned to intensify the inspection process. So far, they say they have found no evidence that Iraq possesses or is developing nuclear, biological or chemical weapons. However, they also say, there are many unanswered questions regarding such issues as alleged chemical weapons and missile engines that have been unaccounted for.