Egyptian police arrested 25-year-old Bat Yam resident Andre Pshenichnikov on Friday and have detained him since, his family said Monday.

It remained unclear as of Monday night under what circumstances Pshenichnikov was arrested after entering Egypt on Friday at the Taba border crossing.

Egyptian security sources told Ynet news late Monday that Pshenichnikov was caught photographing security installations, and tried to find information on managers of the Taba border crossing.

According to Army Radio, he crossed the Egyptian border illegally last week before being captured and handed over to Israeli authorities, who detained him, and after several days released him on condition that he hand over his passports. Pshenichnikov then jumped the border illegally again and was arrested by Egyptian authorities.

Earlier this year, Pshenichnikov, who immigrated with his family from Tajikistan 13 years ago, caused a stir when he declared that he wished to renounce his Israeli citizenship and adopt Palestinian citizenship.

“I hate Zionism,” he told the Associated Press in June. “I want to be part of the Palestinian resistance.”

Pshenichnikov told his girlfriend, who spoke to The Times of Israel on Monday, that he was traveling to Egypt to meet French friends he had met in Paris earlier this year. He called his family on Saturday to inform them that he’d been arrested, but as of Monday they were not sure of his whereabouts. His girlfriend said he had been moved from one detention facility to another, and suggested that he may have been held in Rafah and Port Said.

Svetlana Pshenichnikov, Andre’s mother, told Army Radio that he’d received a visa to enter Egypt last week, but that he’d encountered “a problem with his documents” and was arrested in Egypt.

“They didn’t let us speak much,” she said. “We called the number back that he’d called us from and they said it was not Taba, but Rafah. Now we don’t know what’s happening with him and we can’t speak to him.”

According to Pshenichnikov’s girlfriend, he attempted to enter Egypt last Monday, but Israeli authorities detained him until Thursday — for what she said was no reason. After his release from Israeli detention, he crossed into Egypt and was arrested by the Egyptian police.

Pshenichnikov’s mother said she wasn’t even sure that he was arrested by the police, but that “it could be that he’s [held] by terrorists.”

“I am afraid,” she said. “Perhaps we’ll fly there and find him.”

The Foreign Ministry confirmed that an Israeli was under arrest in Egypt, but could not confirm his identity, and said the matter was under investigation. It said it was communicating with Egyptian authorities, who were being cooperative.

The Egyptian Embassy in Israel was not available for comment.

Pshenichnikov, who served in the IDF for three years, began to question Israel’s relationship with the Palestinians during or after his military service. In April, he moved to the Deheishe refugee camp near the West Bank city of Bethlehem and worked as a waiter in a Bethlehem hotel and as a construction worker in the camp.

In October 2011, American-Israeli Ilan Grapel was released from Egyptian prison in exchange for 25 Egyptians in Israeli jails, after being incarcerated for five months on espionage charges. Grapel was working for an Egyptian NGO that aids refugees from Iraq and Sudan.