NAIROBI - Somalia's new security minister warned foreigners Friday not to visit the Horn of Africa nation without government approval after masked gunmen massacred seven Pakistani preachers at a mosque.

The clerics were killed Wednesday in Galkayo, a town on the southern edge of the semi-autonomous northern Puntland region. Officials in Puntland and neighboring Galmudug district accuse each other of ordering the shooting.

Some residents said the sheikhs may have been suspected of al Qaeda links, while others rejected that and said they were from South Asia's apolitical Tablighi Jamaat religious movement.

Mohamed Abdullahi, who was appointed as security minister last month after his predecessor was assassinated by a suicide bomber in June, said their identity was not yet established.

Foreign fighters have been using this as cover and acting like preachers in Somalia. Nobody is sure if they were real preachers, but we condemn the killing of people in a mosque, he told Reuters in an interview.

I am warning Islamic preachers and all foreigners not to come to Somalia with such arrangements. They have to pass through the country's immigration authorities who can advise them on when they can arrive and where they should stay.

Western security agencies say Somalia has become a haven for Islamist militants plotting attacks in the region and beyond. Violence has killed more than 18,000 civilians since the start of 2007 and driven another 1 million from their homes.

The country has been mired in civil war since 1991, and the administration of President Sheikh Sharif Ahmed controls only small pockets of the bullet-scarred capital Mogadishu.

It is battling hardline Islamist insurgents in southern and central regions, including the al Shabaab group, which the United States accuses of being al Qaeda's proxy in Somalia.

At least 16 people were killed and 20 wounded in two days of fighting between al Shabaab and rival militiamen in the central Galgadud region, witnesses told Reuters by telephone Friday.

Abdullahi said the government was holding indirect talks with three senior al Shabaab commanders and with high profile members of another guerrilla group, Hizbul Islam.

We are getting quite positive signals ... In the coming weeks there will be a good development, he said.

He did not elaborate on the discussions, but said more than 50 Hizbul Islam fighters voluntarily disarmed this week.

They had no deep political ideology. Most of them were brainwashed or forced into what they were doing. They also realized they had lost the moral support of Somalis because of their actions, the minister said.

(Additional reporting by Ibrahim Mohamed in Hargeisa; Writing by Daniel Wallis; Editing by Alison Williams)

Somalia