HANOI, Vietnam >> Police said Monday the wife of a Vietnamese journalist confessed to dousing him in gasoline and torching him in his sleep — a killing his colleagues initially feared was revenge for his investigative reporting.

International media rights groups were outraged at the attack after initial reports said someone broke into the bedroom through a window to set Le Hoang Hung on fire. The 50-year-old reporter worked for Nguoi Lao Dong newspaper, and colleagues feared someone upset by his reporting on corruption or smuggling investigations had targeted him.

State media say police determined Tran Thi Thuy Lieu, 40, gambled frequently and had argued with her husband over money.

Lieu was brought to a police station Sunday night where she admitted killing Hung, said Lt. Col. Pham Van Tien, chief investigator of Long An provincial police. He refused to give more details except that she was being questioned further.

Hung, 50, died Jan. 29 after 10 days of treatment for third-degree burns covering 20 percent of his body.

Monday’s Labor newspaper quoted unidentified police sources as saying Lieu wanted to warn her husband after a dispute over money and did not intend to kill him.

Police have determined that she lost over 1 billion dong ($47,000) during 22 gambling trips to neighboring Cambodia in December, the report said.

Local media have reported that she urged her husband to sell their house in Tan An town, Long An province, but Hung did not agree to the idea.