Liberian secret police looking for a former warlord at the U.S. Embassy sprayed gunfire over the compound, killing at least two people and injuring two Americans, officials said Monday.

The two people killed Saturday were aides to former Liberian warlord Roosevelt Johnson, said Gen. Timothy Shelpidi, the commander of the Nigerian-led peacekeeping force that patrols Liberia. Johnson is a rival of President Charles Taylor."Some of Johnson's men ran into the American Embassy and Liberian security forces opened fire on them," Shelpidi said.

U.S. Embassy officials declined comment.

Johnson had been hiding in the embassy, at least temporarily, according to a State Department official in Washington, who spoke Sunday on condition of anonymity. Liberian government forces told embassy personnel they "will honor the inviolability of the embassy," said the official, who didn't know whether Johnson was still at the U.S. compound late Sunday.

The official confirmed that government forces fired on Johnson's group as they entered the embassy, killing two of his allies and injuring two U.S. workers.

The embassy temporarily suspended operations and authorized the departure of non-emergency personnel and family members of embassy workers.

The State Department also issued a travel advisory Saturday, warning Americans against going to Liberia. At least 33 people were killed Friday and Saturday when the government tried to arrest Johnson.