Pro-Palestinian activists have criticised UK airports and budget airline Jet2 for imposing the UK's "first Israeli checkpoints" after passengers attempting to take part in Sunday's "flytilla" protests were stopped from boarding flights to Israel.

A dozen or so passengers, led by the Scottish Palestine Solidarity Campaign, were stopped by Jet2's Manchester check-in desk, which closed briefly due to a peaceful protest by 100 people, police confirmed. The airline broke with its non-refund policy and offered full refunds after protests. Easyjet also offered refunds to a small number of protesters who attempted to fly from Luton Airport. In statements, both airlines said they had legal obligations not to allow passengers to fly to a country which would bar entry.

Manchester Jewish activist Pia Feig, 59, said protesters were considering legal action against Jet2 and complaints to Manchester's airport authority for discrimination and refusing to honour a binding contract.

"There was a Chasidic family next to me at the check-in desk who were allowed to fly. The only difference between myself and them is my beliefs as an avowed open supporter of the rights of Palestinians." Grandmother Mrs Feig complained: "Under British law, you can't discriminate on goods and services on the basis of belief. Jet2 was the first checkpoint in the West Bank, and we know the checkpoints are part of the system of occupation."

There was confusion among the airlines after 13 UK activists successfully boarded flights to Tel Aviv from Luton and Manchester. The 13 were part of a total of around 80 activists who flew from various countries to reach Bethlehem in the Welcome to Palestine protest. Another Manchester activist was turned back by airport security after reaching the boarding gate, although Paveen Yaqub, who was on the Mavi Marmara, successfully flew with Jet2, but was then held in an Israeli jail. At Luton, three activists said they were not stopped by EasyJet before boarding their flights to Tel Aviv.

‘Jet2 was the first checkpoint in the West Bank’

All protesters were returned from Tel Aviv by their airlines.

Luton protest organiser "D" Murphy, who was imprisoned for six days last August in the first flytilla, said Israel had created negative publicity because of its "overreaction" to people "openly coming in peace."