Congolese security forces killed at least seven protesters and a policeman died amid violence as more than a thousand people demonstrated in the capital Kinshasa against President Joseph Kabila's refusal to step down from power.

Florence Marchal, United Nations Congo mission spokeswoman, said at least 82 people had been arrested across the country in connection with Sunday's protests.

She condemned the use of force against peaceful demonstrators and suppression of rights.

Ida Sawyer, Human Rights Watch Central Africa director, said Congolese security forces shot dead two men outside St Alphonse church in the Matete district.

However, Colonel Pierrot Mwanamputu, Congo police spokesman, said the two were killed after an altercation with police. He said a police officer also died.