KUNMING - Thirty-nine drug addicts escaped from a rehabilitation detention center earlier this month, authorities in southwest China's Yunnan province confirmed Monday.

The drug addicts fled from the center on the morning of April 6 when they were taking part in physical exercise, said a Zhenxiong County government statement.

Police have captured 12 of the runaways and returned them to the center. They are still searching for the remaining 27, the statement said.

Those who were responsible for the escape have been suspended from their posts while an investigation takes place, it added.

Yunnan, which has a 4,060-km-long border with Myanmar, Laos and Vietnam, suffers from the notorious international drug source of the "Golden Triangle."

Border police in Yunnan captured 2,820 suspects in 2,458 drug cases, seizing a total of 4.95 tonnes of narcotics last year, up 43 percent compared with 3.45 tonnes in 2011.