PUEBLO, Colo. (CBS4) – The ex-boyfriend of a pregnant woman who vanished in 2013 is under arrest for her murder.

Pueblo police along with the Colorado Bureau of Investigation arrested Donthe Isiah Lucas in connection with Kelsie Schelling’s murder. Schelling’s body has not been found.

Schelling, 21, disappeared in 2013 after she traveled from Denver to Pueblo to tell her ex-boyfriend, Donthe Lucas, she was pregnant. Her family has long believed she was murdered.

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Kelsie Schelling (credit: CBS)

Lucas, 27, is already in custody for an armed robbery earlier this month. Police say they cannot release details about what led to the arrest of Lucas on the murder charge at this time.