Egyptian police closed the Rafah border crossing with Gaza on Friday in protest at the kidnapping of colleagues in the Sinai peninsula, a security source and witnesses said.
Three policemen and four soldiers were abducted on Thursday by armed men who are demanding the release of a group of prisoners held at a police station in the North Sinai town of El-Arish, official media reported.
The captured policemen worked at the Rafah border terminal, a security source said.
On Friday, their colleagues padlocked the gates leading to the terminal to protest the abductions, witnesses and the security source said.
The protest comes a day after President Mohamed Morsi held crisis talks with his defence and interior ministers over the abductions, and as negotiations to secure the release of the servicemen were underway.
State media has said that security officials were in talks with the abductors via mediators -- local Bedouin leaders who hold sway in the Sinai peninsula.
A spate of hostage-taking has rocked the Sinai, which borders Israel as well as Gaza, but they usually last for no longer than 48 hours and are often carried out by Bedouin seeking the release of jailed relatives.
Such abductions have been on the rise since the 2011 uprising that toppled veteran president Hosni Mubarak.
Islamist militants have taken advantage of a security breakdown after the uprising to use the Sinai as a launchpad for attacks on security forces, a strategic gas export pipeline to Egypt's neighbours and on Israel across the border.
The most serious incident was in August 2011, when gunmen slipped across and staged a series of ambushes that killed eight Israelis.