Two sisters from the Gaza Strip were apprehended at the Erez crossing with explosive materials hidden inside tubes designated for cancer medicine, Israeli officials said Wednesday.

The sisters had obtained a permit to cross into Israel so one of them could receive cancer treatments at an Israeli hospital, The Times of Israel reported. The explosive materials had been “sent by Hamas and it is believed that they were meant to be used to carry out attacks in Israel in the near future,” according to the Shin Bet, Israel’s internal security agency.

It is believed that the substances, which were discovered during a security check, were meant to be used in improvised explosive devices.

“Unfortunately, this is more proof that terror groups in Gaza are continuing to take advantage of humanitarian channels to export terror into Israel’s heartland,” Defense Ministry Crossing Points Authority head Kamil Abu Rokan said in a statement. “The security checks at the crossing worked exactly as we expect and with notable professionalism.”

Last year, more than 30,000 Gazans seeking medical treatment were allowed to cross into Israel.

There have been previous cases of Hamas and other Palestinian terror groups taking advantage of medical permits to attempt terror attacks against Israel.

In one such notable case, Wafa Samir al-Biss, who had been injured in a kitchen gas explosion and was being treated for burns in an Israeli hospital, was caught in 2005 trying to enter Israel at the Erez crossing while wearing an explosive belt. She was recruited by a terror group with links to Fatah and intended to detonate herself inside a crowded Israeli hospital.

[Photo: Zero0000 / WikiCommons ]