The mines include Brazilian-made anti-personnel mines and Egyptian-made anti-tank mines.
Two minefields were discovered by monitors in the days following last Saturday’s retreat from Ajdabiyah by Gaddafi’s troops and appear to be have been laid during their 10-day occupation of the crossroads town 150 km (90 miles) south of the rebel capital Benghazi.
His forces have since reversed the retreat with a counter-attack and were at the gates of Ajdabiyah once again on Thursday.
The first field was sown around electricity pylons a few yards off the Ajdabiyah-Benghazi road in an area of sand near the town’s Eastern Gate, Peter Bouckaert, a Human Rights Watch monitor in Benghazi, told Reuters.
An electrical repair truck hit a mine there on Monday and then another as men tried to pull it out, he said. There were no casualties.
Mine clearers marked out 24 anti-tank mines and 30 to 40 anti-personnel mines, he said, adding that many vehicles and people on foot pass by the area.
A second field with a similar number of mines was found near a clutch of buildings about a kilometre away.
The use of landmines brings a dangerous new dimension to the conflict that has been fought over 100s of kilometres up and down Libya’s main coastal highway linking the east and the west.
The rebel army, made up largely of untrained volunteers and a cavalcade of supporters, is highly undisciplined and is scattered over a wide area behind the vanguard.
Bouckaert said his team had also found stocks of mines abandoned by Gaddafi’s forces.
“We found 12 warehouses of anti-vehicle mines in Benghazi, tens of thousands of them,” he said.
They also came across 35 warehouses full of munitions in Ajdabiyah. They held no stocks of landmines but had vast quantities of artillery shells, mortar bombs and anti-tank missiles.
Libya has not signed the 1997 Mines Ban Treaty, which in any case does not prohibit the use of anti-vehicle mines.
“The only mines that are banned are the anti-personnel mines so they can put as many anti-tank mines as they like. It’s part of the game,” said an international mines expert, who asked not to be identified to protect the confidentiality of his mission.