BOGOTA (Reuters) - A Colombian nun who was kidnapped more than two months ago in Mali is being held by the Macina Liberation Front Islamist militant group, Colombian national police said on Tuesday, citing intelligence reports.

Gloria Cecilia Narvaez was seized by armed men on Feb. 7 in Mali’s southern Karangasso region, where she had been working in a health center. Four people have been charged in her disappearance.

“Intelligence tells us that it is the Macina Liberation Front. We’ll have to wait for a statement from that group to know what they will demand,” General Fernando Murillo, the head of the national police’s anti-kidnapping division, told Reuters.

An international unit led by France is looking for the nun, Murillo said, but she may have been moved out of Mali by her captors, perhaps to neighboring Burkina Faso. The kidnappers have so far sent no proof of life or ransom demands, he added.

“We think she was taken by mistake - that she was not the target,” Murillo said in an interview. Neither Narvaez’s religious order nor her family has the funds to pay a ransom, he said.

The incident is the first time that Colombia, known as a kidnapping capital in the 1990s, has been involved in the search and rescue of one of its citizens in another country.

Malian prosecutors have declined to provide details about the four people charged in the case, but a security source has told Reuters they are connected to the Catholic parish from which Narvaez was abducted. Investigators previously said they suspected Islamist militants could be responsible.

Kidnapping has become a lucrative source of cash for groups like Al Qaeda in the Islamic Maghreb and al Mourabitoun. The latter is suspected of kidnapping a French-Swiss aid worker from the northern city of Gao in December.

The Macina Liberation Front is composed of Fulanis - cattle herders and farmers from central Mali. Its figurehead, Amadou Koufa, is a fiery cleric whose sermons call on Fulanis to rebuild historic empires like Massina, which once stretched over the Mopti region.

Islamist militants, who seized northern Mali in 2012 before being driven back by French forces the following year, have regrouped and are increasingly conducting raids in southern and central Mali, areas previously deemed safe.