The United Nations Children's Fund (UNICEF) warned the leaders of armed groups in the Central African Republic (CAR) on Friday that their continuing recruitment and use of children represented a grave violation of international law.

More than 2,000 boys and girls were estimated to be associated with armed groups before the latest upsurge of fighting began in December last year and recruitment of children has taken place on both sides of confrontations since December, said Marixie Mercado, spokesperson of the UNICEF.

Over the past four months, tension, insecurity and a lack of access by humanitarian workers to large parts of the country left the children in the country at greater risk than ever, Mercado said.

She said that UNICEF has called on the new leadership in the CAR to ensure that all children associated with armed groups to be released immediately.

Since 2007, more than 1,000 children have been released from armed and self-defense groups in the CAR and the UNICEF has provided them with rehabilitation and reintegration services, according to Mercado.