By Kim Ghattas BBC correspondent in Beirut

The Lebanese army may have positions around the Palestinian camp of Ain al-Helweh in south Lebanon as well as checkpoints at all the entrances of the camp.

But Lebanese soldiers will not actually enter the camp to arrest any Palestinian suspect.

The security forces keep clear of the camps

The 12 refugee camps scattered all over the country have been off-bounds to Lebanese troops for decades.

There are always fears of a repeat of the violent clashes that opposed the Lebanese army to Palestinian factions at the onset of the Lebanese civil war in 1975.

The camp of Ain al-Helweh in particular is known for its lawlessness.

Haven for fugitives

Several fugitives wanted by the Lebanese police are thought to be hiding there.

One of them is Abu Mahjan, leader of Osbat al-Ansar, a group also listed by the United States as a terrorist organisation.

The Lebanese army is now waiting for Palestinian factions inside the camp to arrest and hand over the suspect Badieh Hamadeh.

A Lebanese Shiite, Mr Hamadeh is believed to be behind a series of bomb attacks against Lebanese army and police positions in the area.

The latest such attack was on Wednesday.

The death of the three Lebanese officers on Thursday has now come as a harsh reminder of the security problem that the armed factions inside the Palestinian camp continue to represent for Lebanon.