Somali gunmen stormed the office of an aid group and kidnapped two Italian aid workers and a Somali colleague on Wednesday, officials and residents said.

In the latest abduction of foreigners, the gunmen blindfolded the guards, then abducted the aid workers at the offices in Awdigle town, 65 km (40 miles) south of the capital Mogadishu, residents said.

The Italians worked for an aid group called CINS, which carries out agricultural projects. An aid group official said the Italians were a man and a woman.

Kidnapping is a lucrative business in Somalia and abductors generally treat their captives well in anticipation of a hefty ransom.

"The gunmen came in and abducted two Italian colleagues, a man and a lady," said an official from the aid group, speaking on condition of anonymity. One resident said a Somali aid worker was also seized.

Somali gunmen are still holding two aid workers, a Briton and a Kenyan, abducted in April. Earlier this week, gunmen kidnapped a Kenyan university lecturer and have since demanded $100,000 (50,800 pounds) for his return.

The kidnapping of foreigners is relatively rare in southern Somalia because the region, wrecked by 17 years of civil conflict, is too dangerous for most aid workers.

Most of the abductions for ransom occur in the more stable northern regions.