United Nations peacekeeping forces have been conducting joint patrols along the Liberia-Cote d’Ivoire border following reports that former Liberian fighters had crossed over to fight as mercenaries.

The UN Operation in Cote d’Ivoire (ONUCI) and the UN Mission in Liberia (UNMIL) began the surveillance northwest of the town of Tabou on Monday in an operation called MAYO II. A similar exercise, MAYO I, was carried out last June.

“The objective of these patrols is to augment the efficiency of the mission of the UN forces through a good coordination of actions, but above all to see that no more traffic of any kind takes place on the porous border,” said ONUCI Captain Thierry Reymbaut during a trip with the press to the region this week.

The patrols follow news reports out of Liberia that former Liberian fighters were joining rebel forces or government troops as mercenaries. Reymbaut neither confirmed nor denied this.

Cote d’Ivoire has been split in two since a failed coup in September 2002 triggered a brief civil war that divided the country between a rebel-held north and government-run south. Some 10,000 UN and French peacekeepers monitor a buffer zone dividing the country. Recruitment of Liberian mercenaries could signal the potential for renewed conflict, human rights groups say.

In a recent report, the UN humanitarian coordination office (OCHA) said New Forces rebels were reinforcing positions in the west, especially in the region around the border town of Danane “where there was the movement of heavily armed troops”.

Both sides in the Ivorian conflict have used Liberian mercenaries, including children, according to New York-based Human Rights Watch (HRW).

Corinne Dufka, senior West Africa researcher for HRW, said although she could not confirm reports of new recruitment of former Liberian fighters, it would not be out of the ordinary.

“There is a pattern of increased recruitment during times of heightened political tension in Cote d’Ivoire, such as we saw last year prior to the end of President Laurent Gbagbo’s constitutional mandate on October 31,” she said.

A UN-backed peace plan extended Gbagbo’s term for one year. International mediators, including African heads of state, have so far been unable to chart a way forward for Cote d’Ivoire beyond the end of this month. Rebels and the political opposition have said they would not accept an extension of Gbagbo’s term.

Dufka said the concern about recruitment in Cote d’Ivoire is intensified by the lack of reintegration programmes for tens of thousands of former Liberian combatants. Liberia’s 14-year conflict ended in August 2003.

She said the government of President Ellen Johnson-Sirleaf was making a good effort at reintegrating former fighters and vulnerable youths, but as of September nearly 30,000 former fighters still had not entered any reintegration programmes.

“The vulnerabilities faced by Liberian youth are not lost on recruiters on all sides of the Ivorian political military divide,” Dufka said.

Former combatants who might cross the Liberian border to look for work in Cote d’Ivoire find it easy to blend in and avoid detention by UN peacekeepers. The border region is lush with cocoa plantations, whose trails are difficult to patrol.

“When you see the youths, there is nothing to indicate that they are mercenaries,” said one officer with a Senegalese detachment of the UN in Tabou. “They give the impression of going back to their farm work. There is no proof to arrest them.”