The San Diego District Attorney’s Office is seeking the public’s help in identifying the suspect in a Chula Vista homicide that occurred 20 years ago. Ryan Cunningham, 22, was beaten and stabbed on March 20, 2004, while he was sitting on the patio of a busy Chula Vista pizza restaurant, officials said. The District Attorney’s Office released a composite sketch of a suspect in the 2004 fatal stabbing of a 22-year-old man in Chula Vista. (San Diego County District Attorney’s Office) Chula Vista police investigators learned that several parties were being held at La Bella’s Pizza Garden the night of the attack, including a baby shower, prosecutors said Thursday in a news release. “It’s clear that there are witnesses that know who stabbed the victim to death or have other valuable information that can help police and investigators to solve this case, but maybe they are afraid to come forward or simply don’t want to be involved,” District Attorney Summer Stephan said in a statement. According to prosecutors, “several suspects, several of whom were armed with various weapons, walked up to Cunningham and immediately began beating him.” Cunningham fell to the ground where he was eventually stabbed by one of the attackers. He died after being transported to a hospital. Authorities are asking attendees of the restaurant that night to contact investigators to help them with the two-decade-old case and released a composite sketch of the man suspected of stabbing Cunningham. San Diego Crime Stoppers is also offering a reward of up to $1,000 for information that leads to an arrest. “The victim, Ryan Cunningham, lost his life in this senseless murder and his family deserves to have justice,” Stephan said.