Investigators said Monday they've identified the "most likely suspect" who fired a shot that slightly injured Taiwanese President Chen Shui-bian (search) one day before he was narrowly re-elected last March.

But the suspect, Chen Yi-hsiung, drowned shortly after the March 19 shooting and police thought it was a suicide because the man prepared a will just before his death, said Hou You-yi (search), head of the Criminal Investigation.

"We investigated 119 suspects ... and Chen Yi-hsiung was the most likely suspect," Hou told reporters.

Hou said that the suspect was unhappy about the economy and the president's governance and left notes on a desk calendar describing his feelings. The investigator read one that said, "I felt depressed. After Chen Shui-bian became the president, the economy turned bad and we could not sell our house."

Another note said, "If Chen is reelected, I am old and cannot change anything."

Hou added, "We looked for his motive, and we found he was displeased with the social reality."

The pre-election shooting grazed the president's stomach as he was riding in an open-top Jeep in a campaign parade in the southern city of Tainan.

Opposition figures have accused pro-Chen politicians of staging the attack to gain sympathy votes in the March 20 election. Chen repeatedly denied he had anything to do with the shooting.

Hou said video footage shot before the shooting put Chen Yi-hsiung at the scene and an extensive investigation of the weapon used traced it back to the suspect, who purchased his handgun shortly before the shooting.

Hou showed videotapes that featured the suspect, who looked like he was in his late 50s and in a yellow jacket, walking in the street near the shooting scene.

After the shooting, "he ran and then slowed to walk, and then walked quickly. He did not walk toward his home but in the opposition direction," Hou said.

Hou said that the suspect's wife confessed to her that he shot the president. Hou told reporters the women said her husband was quiet for several days after the shooting. After she saw the TV footage of her husband at the scene, she asked him if he did it, Hou said.

"He said, 'I did it and I will handle it myself,"' Hou said quoting the suspect's wife.

The wife said the suspect asked her to trim his hair and sideburns to change his looks.