A Yemen-based al-Qaida group is calling for regional coordination with rebels in Somalia. The governments of both countries are facing powerful insurgencies from Islamist forces.
The deputy commander of the militant group known as al-Qaida in the Arabian Peninsula, Said Ali al-Shihri, has issued an audio statement urging the Somali al-Shabab militants to join with his group in blocking U.S. maritime shipments to Israel.
Yemen sits only 30 kilometers across the ocean from Somalia's smaller northern neighbor Djibouti. The strait connects the Red Sea to the Gulf of Aden, which leads out to the Arabian Sea and Indian Ocean.
Across the gulf in Somalia, a shaky Western-backed government is under siege from rebels who control most of the country's south and much of the capital Mogadishu.
The most powerful of the rebel groups goes by the name al-Shabab, meaning "the youth" in Arabic. It has called for strict sharia law in areas under its control, and its leadership is believed to include a number of foreign Islamist militants.
The stronghold of the radical Somali rebel group is in the southern part of the country, hundreds of kilometers from the Gulf of Aden waters separating the two nations.
The al-Qaida affiliates operating in Yemen made international headlines following a Christmas Day attempt to blow up a U.S. airliner. The Nigerian charged with trying to execute the suicide attack was trained in Yemen. Al-Qaida has claimed responsibility for his plans.
While analysts doubt that the two nations' bands of Islamic militants are currently strongly connected with each other, Western security officials are concerned that the two may forge greater ties and create a regional stronghold for the wider global militant movement.
The seafaring capabilities of Somalis have come under international attention the past few years due to an explosion of organized piracy that has developed off the shorelines of the lawless nation. The illicit industry has resulted in the hijacking of scores of commercial ships, released by the sea bandits once paid a hefty ransom.
The base for this pirate activity is mostly off the northeastern semi-autonomous region of Puntland. These northern pirates are generally not connected to al-Shabab in the South, though some financial ties may exist.
Shihri, a Saudi Arabian, was captured by U.S. forces in 2001 and held in captivity at the U.S. detention center at Guantanamo Bay until 2007, when he was sent back to Saudi Arabia.