Authorities increased security and shut down a southern port in Yemen on Thursday fearing al-Qaida suicide attacks on government and foreign interests, government officials said. An Interior Ministry official said that army was deployed Thursday around government institutions and foreign oil installations after authorities received intelligence that the terror group was planning to carry out suicide attacks in Yemen. The official spoke on condition of anonymity because he was not authorized to speak to the media. In the capital, streets leading to government security buildings were blocked, and military jeeps carrying soldiers with machine guns were deployed near foreign embassies, ambassadors' residents and foreign gas and oil companies. A maritime official in the southern port of Aden said security officials ordered the port to shut down fearing al-Qaida attacks. The maritime official, who also asked to remain anonymous because he was not allowed to talk to the press, said authorities received suicide attack threats early Thursday that targeted the Aden port. He said boats and ships movements were stopped beginning in the morning. Yemen's southern port of Aden had witnessed previous al-Qaida attacks including the Oct. 12, 2000 USS Cole bombing that killed 17 American sailors as their ship was refueling. Two years later, two suicide bombers rammed an explosive-laden boat into the French oil tanker Limburg, killing a Bulgarian crew member and spilling 90,000 barrels of oil into the Gulf of Aden. Yemen was long a haven for Islamic militants. But after the Sept. 11 attacks, the government aligned itself with the US-led war on terrorism. But many diplomats and outside experts have raised questions about Yemen's cooperation and inability to control tribal areas.