Washington(CNN) Two US sailors based at Naval Submarine Base Kings Bay in Georgia have died of apparent drug overdoses in the last week, according to a US Navy public affairs officer.

Petty Officer First Class Brian Jerrell, a sailor assigned to the Trident Training Facility, was found dead of an apparent drug overdose in his off base residence on October 12, Navy Cmdr. Sarah Self-Kyler said.

Four days later, Jerrell's roommate, Petty Officer Second Class Ty Bell, a sailor assigned to the Ohio-class ballistic missile submarine USS Wyoming was found dead of an apparent overdose as well, according to Self-Kyler.

A Navy official said the overdoses were a result of cocaine, but cautioned there is a toxicology report pending.

Kingsland Police Department is investigating the incident, with support by the United States Naval Criminal Investigative Service.

"Tragically, we have lost two sailors in less than a week to apparent drug overdose," Self-Kyler said. "The submarine force and Kings Bay leadership are taking these events seriously" and have ordered a urinalysis sweep of all Kings Bay commands "for opportunities to increase various spot checks (i.e. increasing frequency of urinalysis testing, command-wide unit sweeps, shipboard health and comfort inspections)."

Commanders have been given clear guidance on drug program execution and added that all local commanders will hold "all hands" calls with their crews on the issue following the deaths.