•A daily summary of global reports on security issues.
The move comes amid concerns that Al Qaeda-linked Muslim militants may be launching a new offensive in the restive south. Abu Sayyaf has regularly traded fire with Philippines forces, but Tuesday's blast was the first time in seven years that they had killed US servicemen.
Aided by an estimated 600 US advisers, the Philippines military has in recent years pushed Abu Sayyaf back to its stronghold on two remote islands. (See map of the joint operations area here.)
US-trained Filipino special forces have been trying to eliminate the group, with the help of US unmanned aerial vehicles and high-tech equipment like night goggles.
But dense jungle canopy and an island population that's sympathetic – and often related by blood – to the Abu Sayyaf have made it difficult to finish them off. Back-to-back attacks on Tuesday, including the one that killed two Americans, have shown that the group is still capable of deadly retaliation.
GMA News, a Filipino news site, quoted Philippines military officials as saying Wednesday that the Seabees, military construction experts, were pulled from one village on the island of Jolo. The personnel were helping build two schools and a well there.
The Associated Press quoted the same military official as saying Abu Sayyaf might be stepping up its campaign. After Tuesday's attack, another blast damaged a bridge used by government tanks.
Xinhua reported that Filipino marines would keep the island's other US-funded projects secure, which will continue as planned.
Last week, a Philippines military official told GMA News that Abu Sayyaf was thought to be getting weapons, including rocket-propelled grenades, from "neighboring countries."
Terror experts say Abu Sayyaf has ties with the Indonesia-based Jemaah Islamiyah, a militant that has had some ties to Al Qaeda. Both groups may also be cooperating with militants on the southern Philippines island of Mindanao, where a much larger insurgent group wants to expand an autonomous area for Muslims.
Tuesday's attack came as some Filipino politicians called for all US military personnel to be kicked out of the country, Reuters reports.