HARTFORD, Conn. >> Shortly before Perrie Mason vanished earlier this month, two 911 calls were made from her phone. Dispatchers did not hear anyone on the line and called her back, but still no response, according to her sister.

Four days later, on Aug. 21, the body of the 31-year-old Connecticut mother of two, who recently moved from Hawaii, was found, and her ex-boyfriend was arraigned in court on domestic violence charges in connection with a previous attack against Mason, authorities said. Officials have called the ex-boyfriend, Jason Watson, a prime suspect in her disappearance, but no charges have been filed in connection with her death.

It’s not clear what happened in the moments after the 911 calls to Meriden’s emergency communications center. City police officials have declined to release the 911 recordings as well as any information about their response to the calls, citing the ongoing criminal investigation into Mason’s death.

Relatives, friends and anti-domestic violence advocates have been left to wonder whether more could have been done after the calls and whether Mason’s death could have been prevented. But they say there are no early indications of any mistakes or wrongdoing.

“We want to know more about that,” said Karen Jarmoc, chief executive officer of the Connecticut Coalition Against Domestic Violence. “Generally when someone calls 911, there is a response.”

Mason, who grew up in Kalihi, moved last year to Connecticut, where she worked as a court monitor and ran her own eyelash business. She and her two sons lived with Watson, who is not the boys’ father, and his two children from another relationship.

Watson is detained on $2 million bail. He is charged with strangulation and assault in connection with an Aug. 15 attack when police say he choked Mason to unconsciousness during a fight about two days after they broke up. Horlback said her sister texted her photos of her injuries.

Watson also is charged in another case with violating probation related to a 2008 sexual assault.

Watson has denied harming Mason.