Eleven Palestinians have been arrested in the past two days in Egypt's Sinai area, where clashes have erupted in recent days between militants and security forces, a senior Egyptian security official said Saturday.
The detentions in North Sinai come a day after Egyptian security forces arrested nine "terrorists" in the Sinai, according to state-run Nile TV.
Those nine suspects were Egyptian, rather than Palestinian.
The 11 Palestinians had "entered Sinai illegally through the tunnels and could not return due to our operation and shutting down of tunnels," said the senior security official, who is not authorized to speak about the investigation.
One of those arrested is allegedly involved in weapons dealing, he said, adding that the investigation is ongoing.
"We also located the car that was used by attackers who had fired at Al Reissa checkpoint days back. They had abandoned it during a shoot-out with security forces," he said.
A convoy of Egyptian military jeeps mounted with rocket launchers entered the North Sinai port town of El Arish, about 30 miles from the Gaza border, on Saturday afternoon, heading to support the recent military build-up.
Tensions have soared in the wake of a string of violent acts near the Gaza border.
Last Sunday, 16 Egyptian soldiers were killed and seven others were wounded in an attack near the Rafah border crossing, when assailants with semiautomatic weapons and hand grenades stole two armored vehicles from Egyptian forces and tried to enter Israel.
Militants and Egyptian security forces also clashed at a checkpoint at Al Reissa in North Sinai on Wednesday.