Egyptian Bedouins on Tuesday captured 25 Chinese workers in Sinai to demand the release of Islamist relatives detained over bombings in the peninsula between 2004 and 2006, a security official said.

The Chinese nationals -- technicians and engineers who work for a military-owned cement factory in the Lehfen area of central Sinai -- were abducted on their way to work, the official said.

"The Chinese will not be released until our demands are met," one Bedouin protester told AFP.

The protesters are demanding the release of five Bedouins held in connection with an attack on the tourist resort of Taba in 2004, part of a series of bombings claimed by a previously unknown Islamist group calling itself Al-Tawhid Wal-Jihad.

They say the ruling Supreme Council of the Armed Forces, which took power last year when a popular uprising ousted president Hosni Mubarak, has repeatedly promised to release the Bedouins.

The Chinese are currently being held in a tent in Lehfen, where protesters have been blocking the highway to northeast Sinai for the past three days, the Bedouins said.

Officials from the Chinese embassy in Cairo were headed to Sinai to deal with the incident, China's official Xinhua agency reported.

The 25 are safe and some have been in contact with the embassy by telephone, embassy consular affairs director Zhang Zhizong told Xinhua.

Chinese ambassador Song Aiguo urged officials at the Egyptian interior and defence ministries "to put the safety of Chinese workers first, properly handle the incident and secure their release as soon as possible," Xinhua said.

A security official told AFP authorities were in talks with Bedouin elders to try to resolve the issue.

The major Red Sea beach resorts of Sharm el-Sheikh, Taba and Dahab all witnessed bloody attacks between 2004 and 2006 which killed a total of 130 people.

After the bombings, Mubarak's government launched a massive crackdown in the Sinai, detaining hundreds of Bedouins, some of whom remained in prison for years without trial and complained of torture.

Since the uprising that toppled Mubarak, Egypt has seen sporadic and sometimes deadly unrest coupled with a sharp rise in crime.

The security situation is worst in Sinai, where the resident Bedouin community is heavily armed.

On Saturday, a French tourist was killed and a German wounded during a hold-up at a money exchange bureau in Sharm el-Sheikh.

Tucked between the mountains of the Sinai desert and waters of the Red Sea, Sharm el-Sheikh's glitzy strip of golden beaches, hotels and casinos, diving resorts and golf courses is a major player in Egypt's key tourism industry.

The peninsula has also seen a string of attacks on a pipeline feeding gas to Israel and Jordan, and authorities have repeatedly pledged tougher security measures to protect the installations.

In December, Israeli troops were on very high alert along the Sinai border over fears a cell of gunmen had crossed into southern Israel.

In August, gunmen succeeded in infiltrating Israel and carried out a coordinated series of ambushes on buses and cars on route 12, which runs along the Egyptian border some 20 kilometres (12 miles) north of the Israeli Red Sea resort of Eilat.

Under its 1979 peace treaty with Israel, Egypt is not allowed a military presence in parts of the Sinai, which also neighbours the Gaza Strip.

The sparsely populated region has some of Egypt's most lucrative tourist areas as well as being home to its mostly poor and disaffected Bedouin population.