Five staff members from Medecins Sans Frontieres (MSF) have been taken from a house in northern Syria by an unknown group, the medical humanitarian group said in a statement.

MSF, also known as Doctors Without Borders, has six hospitals and four health centres in northern Syria and provides health support from neighbouring countries to within Syria as well as to Syrian refugees.

The group did not specify the nationality of the staff, their roles, or which group took them, but said it was "in contact with all the relevant stakeholders" and trying to re-establish contact with the staff.

"MSF confirms that five members of its staff were taken yesterday night from an MSF house in the north of Syria by a group, apparently for questioning," spokeswoman Samantha Maurin said in a statement.

"MSF is in contact with all the appropriate stakeholders as well as the families of the colleagues and is doing everything possible to re-establish contact with these colleagues."

MSF is not sanctioned by Damascus to distribute aid in Syria but it does operate in rebel-held areas.

Shadowy group emerges Fighters from an Al Qaeda-linked group calling itself the Islamic State of Iraq and the Levant claim victories in Iraq.

Earlier, unconfirmed reports posted online by activists suggested that jihadist fighters had raided an MSF-supported field hospital in the province of Latakia.

The reports say the militants were from the Al Qaeda-linked insurgent group Islamic State of Iraq and the Levant (ISIL).

In October, seven employees of the International Committee of the Red Cross were kidnapped in the north-western Idlib province, with a Syrian NGO blaming the abduction on the ISIL.

ISIL has been accused of targeting both foreign and Syria journalists as well as aid workers and activists for kidnapping.

The insurgent group was this week reported to have seized partial control of two major Iraqi cities for the first time since the withdrawal of US-led forces.

A United Nations document said in November that 12 UN staff and 32 staff or volunteers of the Syrian Arab Red Crescent have been killed since March 2011, when the crisis started, and 21 UN staff remained in detention.

In September 2013, a Syrian surgeon working for MSF was killed in the north of the country, and aid workers operating in rebel-held parts of Syria have faced detention and kidnappings.

AFP/Reuters