Kenya's internal security minister Friday launched a police internal affairs unit to investigate allegations of abuses in the force including corruption and accusations that officers kill suspects and perpetrate other human rights abuses.The new investigation body has been welcomed with optimism by some rights activists, but many remain skeptical on its ability to bring adequate change.The internal affairs unit will put the police on a "trajectory of reforms," Internal Security Cabinet Secretary Fred Matiangi said. The unit has been launched amid allegations by human rights groups and the public that police killed 22 suspects in the last two weeks in a low-income area of Nairobi.Rights groups have for years claimed that Kenya's police force is riddled with corruption and carries out abuses.Eric Kiraithe, a former police spokesman who is now the government spokesman admitted that corruption in the force saying it "runs deep and wide."The local chapter of the international anti-corruption watchdog Transparency International has for more than a decade ranked the Kenyan police as the most corrupt institution in a country where corruption is endemic.* Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and FacebookThe abuses have continued despite an exercise in which all 100 000 officers are being scrutinized, rights advocates say. At least 2 000 officers have been fired out of around 50,000 scrutinized as the exercise which started in December 2013 and is continuing.When that investigation began, body parts from a person reported kidnapped were sent to the National Police Service Commission with a note warning the chairman to tread carefully.The Independent Medico-Legal Unit, or IMLU, has conducted autopsies on the bodies of the 22 killed by police. "Our preliminary investigations indicate that those were extrajudicial killings," said Peter Kiama, the executive director of the group. "They were not done according to the law. The police were in a position to arrest and not kill those individuals."The IMLU in 2014 documented how a majority of police killings at that time were connected to police extorting money from suspects and not police work. He said human rights defenders who raised concern about the killings are being threatened.Kiama said the internal affairs unit can be effective if given independence and resources."This is a huge investment and the demonstration of political will is a plus," he said, adding that despite the challenges facing the new unit, "there is justification for skepticism but there is space for optimism."