Dozens of protesters gathered outside Downing Street to demand Democratic Republic of Congo (DRC) President Joseph Kabila's departure when his mandate runs out on 19 December.

It follows nationwide demonstrations in Congo yesterday (19 September) which saw at least 17 people – including three police officers – killed as crowds gathered to serve Kabila with three months' notice. Opposition groups say that more than 50 people died in the violence and the headquarters of three of the country's opposition parties were torched overnight and in the early hours of Tuesday (20 September).

Presidential elections were originally scheduled to take place next month, but the vote could be delayed until next year due to a number of outstanding issues, including updating the voting register.

Kabila is accused of trying to hold on to power beyond a second term, which is prohibited under the Congolese constitution. He has been in power since his father was assassinated in 2001.

"We are here to ask the British government to put pressure on Kabila not to seek a third mandate so he has to leave power by 20 December 2016," Theo Ngombo, the UK representative of Congolese opposition party UDPS, told IBTimes UK in Westminster.

"Elections should have been called yesterday. The national body to call the election [CENI] didn't do it and Mr Kabila is manoeuvering and playing with the constitution so he can remain in power behind the fixed term," he added. Yesterday was the deadline for CENI to announce the date for presidential elections.

The UK has repeatedly said that it is ready to help facilitate elections in the DRC both financially and diplomatically, but that ultimate responsibility rests with Kabila's government.

With tensions running high, a spokesman for the Congolese government insisted that there was a criminal element in protester ranks. "Everybody has the right to demonstrate," Lambert Mende told Voice of America (VOA). "Nobody has the right to kill and loot and destroy property. They came just to loot and destroy and kill."

Democratic Republic of Congo DRC
Protesters chant slogans during a march to press President Joseph Kabila to step down Kenny Katombe/Reuters

Another Congolese protester in London said she came to tell the world that the people are unhappy with what is happening in Africa's biggest copper producer. "We have a huge country but people are living worse than animals," Brigitte Kongo told IBTimes UK.

"The people in the government are taking the money for themselves," she added. "Social life, education and health, they are not existing and people are dying." The DRC contains an estimated $24tn (£18.5tn) in untapped mineral wealth yet is somehow home to some of the world's poorest people.

The British government has condemned the narrowing political space in the DRC and urged authorities to respect people's rights to protest. "The Congolese people's democratic right to peaceful protest must be protected," the UK's Minister for Africa and the Middle East, Tobias Ellwood, said from New York yesterday.

"The DRC's constitution is clear that the democratic aspirations of the Congolese people should be met through elections, particularly presidential elections," he added. "The United Kingdom regrets that these elections have not been called three months before the end of the president's term, as the constitution requires. I call on all sides to reach agreement urgently on a date for presidential elections as soon as possible in 2017."

Rights groups have also called on the Congolese government to allow people to protest freely in a country which describes itself as "democratic" in its name.

"Confronting people exercising their rights to freedom of expression, association and assembly with excessive force fans the flames of unrest," a statement from Amnesty International said. "The DRC authorities must take immediate steps to halt this escalating tension, and all parties must refrain from violence."

Click here to watch the protests outside Downing Street in full.