Dutch citizen Joran Van der Sloot plans to wed his pregnant girlfriend from Peru on Friday in prison. He remains the main suspect in the 2005 disappearance of American teenager Natalee Holloway. As of now, he is serving a 28-year sentence for a separate murder.

The 26-year-old plans to marry Leidy Figueroa in Lima's Piedras Gordas penitentiary, his attorney Maximo Altez said on Thursday.

Figueroa, 24, met her soon-to-be husband when she was selling candies and cigarettes in prison. She is expected to give birth to their child in September. Altez said he will be a witness at the ceremony.

Prisoners are granted conjugal visits at Piedras Gordas, an official said (although Van der Sloot managed to get his fiancée pregnant without official visits). 

Van der Sloot was sentenced in 2012 after he confessed to strangling, beating and suffocating Stephany Flores, a 21-year-old Peruvian business student, in 2010. They had met in a casino, Reuters said.

He is widely suspected of another murder -- that of Natalee Holloway, the American girl who disappeared on vacation in Aruba in 2005 after she had just graduated high school. She was 18 years old. She was last seen with him and another man.

Holloway’s body has never been found and Van der Sloot denies any involvement in her disappearance. The U.S. has said it will extradite Van der Sloot for questioning about the Holloway case after he finishes serving his sentence in Peru.

Follow me on Twitter @mariamzzarella