Libyan rebels say forces loyal to Muammar Qaddafi have stepped up the shelling of the rebel-held western city of Misurata, killing at least five people and injuring 25.
Misurata, Libya's third city, is the last major rebel outpost in the west of the country, but has been under siege by government troops.
In the east, rebels claimed that a NATO air strike mistakenly hit one of their tanks. NATO said it was looking into the report.
A representative of the rebels in the eastern stronghold of Benghazi, meanwhile, refuted the Qaddafi government's accusations
that British planes had bombed a major oil field.
Abdeljalil Mayuf, a rebel official, said the Sarir oil field was attacked and damaged by Qaddafi's forces.
Libyan Deputy Foreign Minister Khaled Kaim had said the bombing of the Sarir oil field damaged a pipeline connecting the field to a Mediterranean port.
Britain is part of the NATO force enforcing a UN-mandated no-fly zone over Libya.
Qaddafi is reported to have sent a letter to President Barack Obama, urging the U.S. leader to end what Qaddafi called "an unjust war."
U.S. Secretary of State Hillary Clinton has reiterated the U.S. position that Qaddafi must go.compiled from agency reports