Libyan rebel forces are reportedly advancing westward to the key city of Brega, after having taken control of oil port Ajdabiya, largely due to air strikes by western coalition forces.

Other reports allege rebel soldiers have already seized Brega.

We are in the center of Brega, Abdelsalam al-Maadani, a rebel fighter, told the Agence France Presse by telephone.

But Reuters said rebels were only at the outskirts of Brega.

In any case, it would appear that western air raids are reducing the effectiveness of Moammar Gaddafi’s state forces.

However, Gaddafi’s soldiers are reportedly shelling to rebel-held town of Misrata. Although other reports said the attack stopped when coalition aircraft were seen flying overhead.

The shelling has stopped and now the war planes of allies are above the sky of Misrata. The shelling stopped when the planes appeared in the sky, one rebel told Reuters.

Indeed, French officials its fighter jets destroyed at least five military planes and two helicopters at the Misrata air base.

Ahmed Al Misrati, an activist in Misrata, told Al Jazeera the town was besieged from all sides.

Since morning [Misrata] has been under heavy gunfire and heavy bombardment ... by tanks or mortar shells, he said. This bombardment is indiscriminate and arbitrary, sometimes targeting residential plots and one entire family was killed - the father and his children. They [Gaddafi troops] are also stationed in other rooftops, especially the high buildings ... Anybody in the street comes under heavy gunfire and now the situation is exacerbating and is very, very dire.”

Earlier, British RAF Tornado airplanes pounded the now-liberated city of Ajdabiya.

Reportedly, triumphant rebels in Ajdabiya chanted Thank you, Obama, Thank you, Cameron.”

Meanwhile, US President Barack Obama said that the clear and focused military campaign in Libya is succeeding.

Make no mistake, because we acted quickly, a humanitarian catastrophe has been avoided and the lives of countless civilians - innocent men, women and children - have been saved, he said.