More than a dozen people who were arrested during a protest against Zimbabwe’s regime appeared in court on Tuesday with injuries they say were inflicted in custody.

Jeremiah Bamu, from Zimbabwe Lawyers for Human Rights, said that some were in a “critical condition” and should be in hospital. “Some of them are appearing in court this afternoon with bandages on their heads,” he said.

One of those arrested, Gift Siziba, a 26-year-old student at the University of Zimbabwe, cannot use either of his hands. Bones in both hands are believed to be broken.

Most of those who were assaulted say they were grabbed from the streets of the capital, Harare, or hauled off buses and taken to the headquarters of President Robert Mugabe’s Zanu-PF party. Once there, they were attacked by men in plainclothes.

Later, they were handed over to police who locked them up in Harare Central Police Station. Some were bleeding and in agony.

A large demonstration against Zimbabwe’s discredited electoral system took place in the capital last Friday. Police and soldiers responded with tear gas, water cannon and baton charges.