US Navy forces have been deployed off the Somali coast to prevent the escape of Islamist militant leaders.
Kenya has also stepped up its border security in order to stop an influx of fighters who are looking to flee the country.
The past two weeks have seen Ethiopian troops push Islamist fighters out of areas they had held for six months.
US State Department spokesman Sean McCormack said the US administration was working closely with its allies in the region to stop Islamists with ties to terrorist organisations from getting away.
The Ethiopian Foreign Minister, Raphael Tuju, told a press conference that Ethiopian troops had detained suspected Islamists holding British, Danish, Canadian and Eritrean passports.
Mr Tuju said that some of these fighters had tried to send their families to Kenya while they remained to 'destabilise the lawful government of Somalia'.
This morning, militiamen fired a rocket at an oil tanker truck near Mogadishu, wounding several people in the first major attack since government forces took the Somali capital last week.
