DAKAR (Reuters) - A new armed group in Central African Republic has killed at least 50 civilians and displaced around 17,000 in a growing campaign to control parts of the country’s northwest, Human Rights Watch (HRW) said in a report on Tuesday.

The emergence of “Return, Reclamation, Rehabilitation”, or 3R, underlines problems facing President Faustin-Archange Touadera, who came to power in March hoping to promote reconciliation, extend the government’s writ across the country and persuade militias to disarm.

The group appeared in late 2015 to protect the minority Peul population, who are mostly Muslim cattle herders, from attacks by Christian anti-balaka militias. It now has hundreds of well-armed fighters who control territory near Cameroon’s border, HRW said.

“They told us they were ready to move into other parts of the northwest and I think it should be taken seriously,” said HRW researcher Lewis Mudge, adding that there is evidence the group has set up road taxes to finance its operations.

“This (group) is a reflection of general instability in the country,” he said.

Central African Republic descended into chaos in 2013 when mainly Muslim Seleka rebels seized power in the majority Christian nation, ousting then-President Francois Bozize and sparking a backlash from Christian anti-balaka militias.

Since France ended a 3-year peacekeeping mission in October, maintaining security has fallen largely to MINUSCA, a 13,000-strong United Nations peacekeeping force that civilians say does not do enough to protect them.

In September, 3R attacked the town of De Gaulle, capital of the Koui sub-prefecture with about 20,000 people, and chased out local authorities despite U.N. troops in the town, HRW said.

The group has also burned villages and raped women and girls in an apparent bid to punish local communities for perceived anti-balaka support, Mudge added.

The U.N. said last week that violence had “grown more severe and widespread.” Clashes in November in the eastern town of Bria were the deadliest in recent months.