Hong Kong  - Medical data on almost 700 Hong Kong children and teenagers with social and developmental problems have been lost, the territory's government admitted Friday.

The records were held on a memory card which was stolen from an unlocked room at a Child Assessment Centre in the city's Tuen Mun district, the government's Department of Health said.

The lost data included detailed records of interviews with troubled youngsters including assessments and, in some cases, their photos, identity card numbers and addresses.

Hong Kong's Deputy Director of Health Gloria Tam apologized to the families affected and said they should contact police if anyone suspicious approached them with their personal details.

As the case involved personal privacy, the affected families should remain alert and report to the police if they were approached by suspicious people with their personal data, she said.

"We have reminded our staff about the absolute importance of office security and to strictly adhere to the government's security regulations," she said in a statement.

A government hotline has been set up to deal with calls from youngsters and family members concerned over the loss of the data, she added. (dpa)