Grocery store owner David Chen is charged with assault and forcible confinement after catching a man who tried to steal from his store in Toronto's Chinatown. (CBC)

A Toronto grocery store owner and two relatives have pleaded not guilty in a case that has made headlines across the country.

David Chen, his cousin and his nephew are charged with assault and forcible confinement in a case that received national attention when it was discovered they had been arrested after catching a thief who had stolen from their store in Chinatown.

Anthony Bennett, the man nabbed by Chen, pleaded guilty in August 2009 to stealing from Chen's Lucky Moose Food Mart on Dundas Street West and was sentenced to 30 days in jail.

In the May 23, 2009, incident, Bennett was initially caught on security footage stealing from the store. When he returned an hour later, Chen, 36, and other two men grabbed him, tied him up and locked him in the back of a delivery van.

The trial was supposed to start Monday, but was delayed because one of Chen's co-accused didn't have an accredited Mandarin translator to help him in court.

Witness called 911

The first witness called when the trial resumed on Wednesday was Erasmus Lopez, who testified he called 911 after he heard screams and saw four Asian men kicking a man.

Bennett, the second witness, admitted to an extensive criminal record going back to 1976, including two theft charges laid on May 23, 2009.

On the day in question, Bennett said, he was approached by a man who asked whether he had stolen anything. "I said 'No'. Then I dropped my bike and ran," he testified.

Bennett said he feared for his life after he was tied, put in back of a van and men began beating him. When police arrived, Bennett testified, "I felt rescued … I was so happy to see them."

Under cross-examination, Bennett admitted he had stolen from Chen earlier that day — and had returned to take more.

Admission helps defence: lawyer

Chen's lawyer Peter Lindsay said that admission changes everything.

"Getting him to admit that he came back to steal is important because that puts him in the act of a crime at the time of chase and at the time of detention," he said. "That's good from my point of view. I didn't expect him to say that, frankly."

The only man Bennett could identify in court was Chen.

Chen was initially charged with kidnapping, carrying a dangerous weapon (a boxcutter), assault and forcible confinement.

Crown prosecutors later dropped the kidnapping and weapon charges but said they would proceed with the charges of forcible confinement and assault.

According to the Criminal Code, a property owner can only make a citizen's arrest if the alleged wrongdoer is caught in the act. The Crown rejects Chen's defence that he was simply conducting a citizen's arrest.

Their trial came to a sudden halt on Monday just a few hours after it began, when the court discovered it did not have an accredited Mandarin interpreter.