Sana’a: Gunmen kidnapped a married Western couple working at the United Nations office in the Hada district of Yemen’s capital Sana’a, where many diplomatic missions are located, a local police source said on Tuesday.

The source gave no further details. There was no immediate word on the diplomat’s nationality or the identity of the woman.

Witnesses reported that the diplomat’s car, apparently armoured, was sandwiched between a van and a taxi behind it.

The diplomat and the woman stepped out of their car to argue with those aboard the two vehicles that had blocked their way. Gunmen then emerged from the taxi, seized the pair and drove them off in the two vehicles.

Kidnapping is common in US-allied Yemen, where the government is struggling to contain an insurgency from Islamists linked to Al Qaida, a southern separatist movement, fighting in the country’s north, and sporadic conflicts with armed tribes.

Hostage-taking is sometimes carried out by militants aiming to intimidate Westerners, but is also used as a tactic by tribesmen to resolve disputes with the government, and by opportunists hoping to sell hostages on to other groups.

Three foreigners, including a Czech doctor, a British oil worker and a German were seized in February.

But in recent years, Al Qaida’s Yemen affiliate, regarded by Washington as its most dangerous, has brought a new, more threatening twist to the kidnappings.

The group has been holding a South African teacher since May last year. It is also still holding a Saudi deputy consul kidnapped in the southern city of Aden in 2012.

Iranian embassy staffer, Nour Ahmad Nikbakht, who was abducted by suspected Al Qaida militants in Sana’a last July, also remains in captivity, tribal sources say.

Yemen, which borders oil giant Saudi Arabia, has long wrestled with instability, internal conflicts and poor governance.

The United States, along with some other Western and Gulf countries, is working with an interim government to effect a political transition after former president Ali Abdullah Saleh was forced from office in 2012 by street protests.