Police have begun ordering Palestinian laborers with legal work permits off buses from the Tel Aviv area to the West Bank, following complaints from settlers that Palestinians pose a security risk by riding the same buses as them.

The Transportation Ministry says it is considering adding bus lines between West Bank roadblocks and central Israel; these would be geared toward Palestinian laborers. Still, such a plan would take at least a few months to go into effect.

Earlier this month a bus operated by Afikim, a company with a government tender to serve West Bank settlements, pulled up at a police roadblock near the settlement of Elkana. The police, who later cited security reasons, ordered all the Palestinian passengers off - leaving them to walk several kilometers to the nearest checkpoint and pay for a taxi home, said an Israeli army reservist who was posted at the checkpoint.

He told Haaretz that the laborers, most of whom work in the Tel Aviv area and usually take the bus home, were angered by the incident. That wasn't the only time the workers were pulled off the bus, though.

"Friends at the checkpoint told me that the same thing happened the next day," said the reservist. "The police confiscated their ID cards, brought the IDs to the checkpoint, and the Palestinians had to get off the bus again and walk several kilometers to the checkpoint."

When asked about the incidents, the police said they wanted to make sure Palestinian workers were returning to the West Bank from the same place they left it. They said it was necessary to "close the circle" to ensure the Palestinians weren't staying in Israel overnight, which requires a separate permit.

"The fact that a laborer has a legal work permit doesn't allow him to travel directly to the territories without going through an established crossing point," the police said in a statement. "That's why there is enforcement activity, for security purposes."

The number of Palestinians working in Israel has increased in the past two years to 29,000 a day, up from 22,000 in 2010.

Palestinian workers generally do not enter the settlements to get on and off the bus, since that would require special authorization. Usually they get on and off along the Trans-Samaria Highway (Route 5).

All the same, Ron Nachman, the mayor of the West Bank settlement of Ariel, has announced on his Facebook page that he has spoken with the army, police and Transportation Ministry about "stopping Palestinians from boarding the buses that go to Ariel."

"All of them are working on this problem, and we hope that they will soon find a solution to the reality that is bothering our people," he wrote.

Commenters left offensive responses to the post, with one referring to the Palestinian passengers as terrorists and another as monkeys.

"On the Ariel lines there are more terrorists than Jewish residents," said one. A woman wrote that she couldn't visit her parents in Ariel because she was too scared to get on the bus, and another commenter said "finally you remembered that we have buses filled with Arabs?"