HONG KONG — One mother fell to her knees before riot police officers and begged for her daughter’s release. Another promised she would boil soup for a trapped son before he made a desperate escape across police lines . From a distance, a father got his first glimpse of his son in days — as the son was led away in handcuffs.

As the police siege of Hong Kong Polytechnic University trapped more than 1,000 pro-democracy protesters this week, another group entangled in the city’s crisis has turned conspicuously outspoken: their parents.

The voices of mothers and fathers, racked by fear and anger, emerged as a call for compromise in the standoff on the campus, where on Tuesday several dozen holdouts remained.

Many parents worried not only about the safety of students in Hong Kong’s increasingly violent protests, but also about the longer-term consequences for young adults whose lives could now be upended by abruptly truncated educations, criminal charges and prison.