The residential building in Ho Man Tin. (Sing Tao photo)

The body of a female security guard in her 40s has been found in a water tank at Mandarin Court on 126-128 Argyle Street in Ho Man Tin today.

A security guard of the residential building alerted police at about 2:00pm, saying that his colleague was missing. The body was found after officers searched the premises.

The search was conducted after surveillance camera footage showed that the woman never left the building since starting her shift on Sunday morning, RTHK reported, citing sources. A knife was found in the tank by police, according to the report.