Kenyan police have offered a reward of 1 million shillings ($7,700; £5,700) for information leading to the arrest of suspected serial killer Collins Jumaisi Khalusha, more than a year after he escaped from their custody.

Khalusha was the prime suspect in the murder of more than 40 women whose mutilated bodies were discovered in a disused quarry that became a dumpsite in the capital, Nairobi.

Shortly after his arrest, he escaped from custody, along with 12 others, after reportedly cutting through a wire mesh roof and scaling a perimeter wall.

This incident prompted outrage, as police faced a renewed backlash over their failure to hunt down Khalusha more than a year later.

Many Kenyans are questioning how he could have escaped from what is regarded as one of the most secure police stations, located near the US embassy and UN offices in Nairobi.

Khalid Hussein, a local activist, criticized the police's commitment to solving the murders and alleged that some bodies remain in the quarry, deteriorating.

Mr. Hussein suggested the police's announcement of the reward was a reactive measure following a documentary highlighting their inaction. He dismissed the reward as "absolutely useless."

According to police spokesman Michael Muchiri, the Directorate of Criminal Investigations (DCI) had previously addressed the complexities involved in the case and is on track to resolve it. The DCI stated that the reward would be awarded for credible information leading to Khalusha's re-arrest.

Last year, police also offered a reward but did not disclose the amount. While several policemen initially arrested for allegedly aiding Khalusha's escape were later released on bail, many Kenyans remain skeptical about the police's capability to detect ongoing crimes near the police station.

Khalusha confessed to his crimes under distressing conditions, according to his lawyer, who claimed that he was tortured into confessing. At the time of his arrest, DCI chief Mohamed Amin admitted they were dealing with a psychopathic serial killer.

The Interior Minister described Khalusha’s escape as “regrettable” and a “sad story,” expressing hope for his arrest.