An employee at a Moraga massage parlor was arrested Thursday on suspicion of soliciting prostitution, police said today. Situ Li, 52, was arrested for alleged misdemeanor solicitation of prostitution at the at the Wonderful Spa in the Rheem Shopping Center at 450 Center St., police said. Li, a San Leandro resident, was taken to the Moraga Police Department and released on a promise to appear in court. Police said officers arrested the woman after conducting an undercover operation to investigate possible illicit activity at the spa around 5 p.m. Thursday. Investigators continue to look into whether the business violated any permits.