CHARLOTTE, N.C. -- Violence at schools and on school buses is sparking questions about student safety at Charlotte-Mecklenburg

Just last month, NBC Charlotte reported on the rising number of guns brought to school last year, according to state numbers.

This week, police records describe students fighting on buses and bringing weapons to school.

Last week, officers responded to Idlewild Elementary School to a student with a butter knife at the bus stop who then went on to punch a student on the bus, records show.

The same week, there were students fighting on a school bus near the 2700 block of Selwyn Road, according to police. Those involved in that incident were sent to a juvenile diversion program.

In addition to those cases, officers found a student with a pocket knife at Croft Community School last week.

Then on Wednesday, police say another student had a pocket knife at Joseph W. Grier Academy.

State numbers from last year show more than 300 weapons possession incidents at CMS for the 2015-2016 school year. There were also three assaults resulting in serious injury and two assaults involving a weapon.

CMS leaders were not available for an on camera interview, but they say the vast majority of students abide by their code of conduct. They also say those who do not follow school behavioral guidelines are disciplined.