KINSHASA, Congo (AP) — Three people were injured Tuesday when men armed with stones and batons descended on an opposition rally in the capital that was demanding that President Joseph Kabila leave office when his term expires next year, a government spokesman said.

The government was working to identify those behind the attack, Lambert Mende said Tuesday evening.

"The government condemns the violence regardless of where it comes from, whether from the government or the opposition," Mende said.

An Associated Press reporter saw the plainclothes assailants attack some of the more than 1,000 people who had gathered.

It was the first large-scale opposition rally in Kinshasa since thousands took to the streets in January to condemn a proposed revision to the electoral law that was perceived as an attempt by Kabila to stay in power beyond 2016.

More than 40 people were killed when security forces cracked down on those demonstrations, the majority of them in the capital, Human Rights Watch said.

The revision was scrapped, but Kabila's opponents still suspect the president may try to stay on beyond his mandate by delaying next year's vote. He has not said directly what his plans are.

Before the attack, opposition politician Vital Kamerhe told the crowd that Kabila's rivals weren't interested in the government's attempts to start a dialogue. Instead he demanded that Kabila respect the constitution and free pro-democracy activists arrested earlier this year.

On Monday representatives of seven political parties that are part of the ruling coalition addressed a letter to Kabila that also implored him to respect existing term limits.