Parents believe a Bronx school is holding back answers after a fourth bomb threat was made in the last two weeks.

They say they want answers as to why bomb threats keep happening at P.S. 20. Parents tell News 12 that the school hasn’t been communicating with them.

School officials say they don’t know who is behind the threats.

A fourth threat was made on Monday, just after another one on Friday. Some parents say they are worried and have had to leave work early to go to school, only to wait a long time to figure out what’s happening.

News 12 reached out to the Department of Education and they responded with a statement saying, "The safety of our students and staff is our top priority. NYPD quickly investigated this threat and deemed it noncredible. Students returned to class."

News 12 has also reached out to the NYPD and they responded with a statement saying, "The 52 Pct detective squad is investigating a bomb threat that was called into PS 20. This is the 4th such incident that occurred at that school."