By Daud Yussuf

GARISSA, Kenya (Reuters) – Heavily armed Somali gunmen kidnapped two European nuns on Monday during a pre-dawn raid on a remote Kenyan border town, witnesses said.

Somalia is one of the most dangerous countries in the world for aid workers, who are often abducted or killed in attacks usually blamed on Islamist insurgents or clan militia.

One local aid worker in the small town of El Wak said the attackers hurled a grenade and then fired a rocket at a Kenyan police post at about 1 a.m. (2200 GMT Sunday).

“They started spraying bullets … then they abducted the Dutch woman and Italian woman from the local church,” he said.

The Kenyan Red Cross Society said in a statement that the gunmen had escaped in three hijacked vehicles, and that it was feared they had taken their captives back across the border.

There was no immediate comment from Kenyan authorities.

Sheikh Hassan Hussein, chairman of Somalia’s neighbouring Gedo Region, said he did not know where they had gone.

“We don’t know who exactly they were, but we can call them Somali bandits,” Hussein told Reuters by telephone.

In the most recent attack on humanitarian workers in lawless Somalia, men armed with pistols in Jamame, north of rebel-held Kismayu port, assassinated a Somali man on Sunday who ran the local office of the U.S.-based Mercy Corps charity.

Gunmen also stormed an airstrip last week in central Somalia, kidnapping four European aid workers and two Kenyan pilots. Locals said the hostages were taken to Mogadishu.

Suspicion for such attacks normally falls on Islamist militants or clan militia, but rebel leaders have said government hardliners are behind the killings to discredit them and stir the international community to intervene. (Additional reporting by Somalia team; Writing by Daniel Wallis)