A former 911 operator has been jailed after being found guilty of hanging up on thousands of emergency telephone calls.

Crenshanda Williams, from Houston, Texas, was sentenced to 10 days in prison and 18 months on probation at Harris County court on Wednesday.

The 44-year-old systematically hung up on emergency calls, including reports of robberies, speeding vehicles and murders, records showed.

Williams worked as an operator at the Houston Emergency Centre for a year-and-a-half before she was caught and fired in August 2016.

Her actions were exposed after emergency centre officials performing monthly audits of 911 calls noticed a high proportion of her calls lasted less than 20 seconds.

These included one where a caller tried to report a violent robbery, and another relating to two drivers racing on the Interstate 45 highway where people had been killed speeding just weeks earlier.

Franklin Bynum, Williams’ attorney, told the court his client was “going through a hard time in her life”.

She told investigators that she hung up because at the time she did not feel like speaking to callers.

"Citizens rely on 911 operators to dispatch help in their time of need. When a public servant betrays the community's trust and breaks the law, we have a responsibility to hold them criminally accountable," Assistant District Attorney Lauren Reeder said in a statement.