Egypt’s presidential spokesman stated Sunday that the president is scheduled to meet with heads of political parties and political figures to discuss ways of solving the issue of kidnapped soldiers in the Sinai Peninsula.

On Thursday, seven Egyptian security personnel, including one member of the armed forces, four port security officers, and two state security officers, were kidnapped by unknown assailants in Sinai.

A security source has revealed that the kidnappers have demanded the release of Islamist militants detained for almost two years.

The militants, who allegedly belong to the Tawhid wal-Jihad group, were convicted of killing five security officers and one civilian during a string of attacks in June/July 2011 on an Al-Arish city police station and a North Sinai branch of the Bank of Alexandria. Twenty-five individuals were charged in the case.

The security source, who asked not to be named, added that the kidnappers have accused Egyptian security forces of torturing one of the detained men.

Notably, a joint media statement was issued by former MP Amr Hamzawy, Mohamed Abou El-Ghar, the head of the Egyptian Social Democratic Party, and Ahmed Saeed, the head of the Free Egyptians Party, announcing that they will not participate in the Morsi meeting.

In the statement, the opposition figures expressed their surprise with the ”non-understandable way of dealing with the opposition,” objecting that it has been excluded from discussing of crucial cases and laws.

Last Thurday, a presidential statement was released following President Mohamed Morsi's meeting with security officials promising to exert "serious efforts" to resolve outstanding security issues in Sinai, including grievances aired by Bedouin tribesmen regarding the lack of development in the peninsula.

The meeting included Defence Minister Abdel-Fattah El-Sisi, Interior Minister Mohamed Ibrahim and General Intelligence chief Raafat Shehata.

Angry policemen have been blocking Rafah Crossing since Friday, demanding the release of their kidnapped colleagues. 

On Sunday, Egyptian police also closed Al-Ouga Crossing between Egypt and Israel in support of their protesting colleagues in Rafah.

A number of tourists have been kidnapped in Sinai this year, after which abductors usually demand the release of detained colleagues in return for the tourists' release.

Thursday's kidnapping, however, represents the first time for security personnel to be abducted by Sinai-based militants.

The restive Egypt-Gaza border region has witnessed an upswing in violence over the course of the past few months, with frequent clashes between security forces and militants.

Authorities have not yet been able to determine the identity of assailants who killed 16 Egyptian soldiers in August, 2012.