Washington, Apr 18 (IANS): The US State Department has ordered the families of the Americembassy staff members to leave N'Djamena, the capital of Chad.

The Department on Saturday ordered non-emergency US government employees to leave the city due to civil unrest and armed violence, reports DPA news agency.

"Armed non-governmental groups in northern Chad have moved south and appear to be heading toward N'Djamena.

"Due to their growing proximity to N'Djamena, and the possibility for violence in the city, non-essential US government employees have been ordered to leave Chad by commercial airline," an advisory read.

"US citizens in Chad wishing to depart should take advantage of commercial flights."

It warned that the government of Chad may impose travel restrictions without notice, which may affect travel plans.

At least 55 people were killed and more than 40 injured as three villages were burned during fighting in the central African country, a governor told DPA on Friday.