Two news photographers were killed in the conflict zone in Libyan rebel stronghold of Misrata where Muammar Gaddafi's forces have intensified attacks on rebel positions.

One of the dead, Tim Hetherington, was a British photographer who made a documentary that was shortlisted for Oscar awards. He was in Misrata to cover the conflict for Vanity Fair magazine.

The other journalist to be killed, Chris Hondros, was a New York-based photographer for Getty Images. Sky News reported that at least three other journalists have been wounded in attacks.

A day before he was killed, Hetherington had posted on his Twitter profile: In besieged Libyan city of Misrata. Indiscriminate shelling by Qaddafi forces. No sign of Nato.

The 41-year-old shutterbug had won the World Press Photo of the Year Award in 2007.

Two other journalists were killed in Misrata in the last month, according to the Committee for the Protection of Journalists (CPJ). They were Al Jazeera cameraman Ali Hassan al Jaber and Mohammed al Nabbous, founder of the online Libya Al-Hurra TV.