A man who is believed to have raped and impregnated his 13-year-old deaf, blind and mute sister in Uganda has been found dead in a lake.

Sanyu was attacked in 2007 and she gave birth the following year. Because of her disability, she was unable to identify her rapist so her mother called for DNA testing of her father and three brothers - the only men in contact with her.

The Ugandan police did not take DNA samples and the government did not respond to a test request by Legal Action for Persons with Disabilities, which was contacted by Sanyu's mother. The case was then closed.

However, three years later Human rights group Equality Now raised funds for the DNA test and findings showed the baby's father was genetically of the same paternal line. Following pressure from the group and media attention, police re-opened the case.

Tests showed that Sanyu's father and two of her brothers were not responsible. But the third brother, who had run away from home, was not tested.

Police made no effort to trace the missing brother but he was recently found dead in a lake. Equality Now is calling for a DNA test to prove he raped and impregnated the teenager and get Sanyu justice.

Disabled girls vulnerable to rape

The brother has already been buried so Equality Now and LAPD want his clothes tested.

Muthoni Muriithi, programme officer at Equality Now, said: "Equality Now and our partners are seriously disturbed by the lack of a thorough investigation and the five-year delay in ensuring justice for Sanyu.

"To ensure that Sanyu and other girls in similar situations get justice, Equality Now calls on the government of Uganda to conduct DNA testing on the body of the remaining suspect at its own expense without delay and to take additional steps to improve the investigation process and prosecution rate in sexual violence cases involving victims with disabilities."

By not continuing the investigation, the group says the Ugandan government is enabling continued impunity for Sanyu's attacker.

Sexual violence is widespread in Uganda and disabled girls and women are particularly vulnerable. For a quarter of women between the ages of 15 and 49, rape is their first experience of sexual intercourse.

Muriithi added: "[The 2006 Ugandan Demographic and Health Survey showed] 20 percent of Ugandans have disabilities. The government, however, does not take the additional steps needed to ensure justice for disabled victims of sexual violence by implementing investigative techniques that would help facilitate the process."