Prosecutors in California amended the charges against a set of San Jose twins who were arrested in connection with the stabbing death of a 22-year-old man after they determined the wrong twin was charged with murder.

Last month, San Jose Police arrested 18-year-old twin brothers Anh and Ductrung Tong following the fatal stabbing of San Jose State University student Richard Phan at a birthday party. As police told KTVU:

...Witnesses said they were not sure which of the twin brothers stabbed Phan because they looked so much alike.

The two have been in custody since Jan. 26.

Ductrung Tong had been charged with murder, but those charges were amended in Santa Clara Superior Court Wednesday. He will now be tried as an accessory to murder. His brother, Anh Tong, now faces murder charges.

“A jury is going to look at this case now with some skepticism because the prosecution’s theory has completely shifted by changing their theory from one twin to the other,” Clarke told CBS San Francisco.

The development happened after closed door meetings during what was to be Ductrung Trong's plea hearing on Wednesday. Prosecutors would not say if the brothers had attempted to mislead investigators.