Los Angeles County District Attorney Steve Cooley told local reporters on Friday that if the two defendants charged with murdering two Chinese students at University of Southern California (USC) were convicted, they will face the death penalty or life without parole.

However, Cooley said prosecutors will have to wait till after the preliminary hearing to ask formally for the death penalty.

On April 11, graduate students Ming Qu and Ying Wu from China were shot while sitting in a BMW about a mile away from USC. Both victims were 23 years old.

Javier Bolden, 19, and Bryan Barnes, 20, were arrested in May on suspicion of killing the students during an apparent robbery attempt.

Almost two months after their arrest, the two defendants have not been arraigned, and it is said that they would only receive a penalty of 20 years in jail even when convicted.

This has angered students at USC and the Chinese community in the United States.There are about 38,000 students attending USC from foreign countries and regions, 2,500 are from China. The school has more international students than any other US universities.

Chinese students at USC started a campaign to gather signatures for a petition to urge prosecutors to prosecute the killers to the full extent and protect the safety of the Chinese students.

In over a month, about 7,000 signatures have been collected. Howard Wang, president of South West Chinese Students and Scholars Association, handed the petition to the Los Angeles County District Attorney's Office Friday and asked the office to convey the concerns and demands to the prosecutors and the judges.

Cooley said that he fully understands the concerns of overseas Chinese students in the US and their parents in China and will make full efforts to prosecute the defendants.

However he said the process will take about one year.

Till now the motive for the shootings of the two Chinese students was still under investigation, according to the police, but the evidence points to a street robbery.