UPDATE 4/14: EMS officials say another theft involving one of its ambulance medication boxes took place during a turnover at Sentara Princess Anne Hospital last week.
A pharmacy technician noticed one of the drug boxes was opened last Monday and narcotics were missing, according to the search warrant.
The missing drugs included morphine, Valium, Versev and Ativan.
A criminal investigation regarding the string of thefts is currently underway, according to Virginia Beach EMS spokesperson Ed Brazle.
Officials say there have been no confirmed break-ins aboard the ambulances since the incidents in mid-March.
UPDATE 3/14: More drugs were stolen from an ambulance medication box at the General Booth Station 21 in Virginia Beach Thursday afternoon, according to Ed Brazle.
Brazle called the continued theft frustrating.
'It's hard to speculate, but this person doing it multiple times in one day and then later in the week, I'm nervous about it happening again,' he said.
Statistics from the Virginia Office of Emergency Medical Services show the problem is on the rise across the state. There was just one reported drug theft from an ambulance in 2007. That number ballooned to 38 in 2013.
VIRGINIA BEACH -- Virginia Beach Police are investigating after drugs turned up missing Tuesday on three different ambulances.
Virginia Beach EMS spokesman Ed Brazle said the three ambulances belong to the Princess Anne Courthouse Rescue Squad, which were being housed at stations 13 and 21.
Brazle said crews first noticed the theft during their routine check at the start of their early shift.
During the check, Brazle said, they noticed the drug box had been tampered with and was missing certain drugs.
That led to a check of all ambulances and fire trucks in Virginia Beach, which turned up two more drug boxes with missing medication.
One of the three ambulances involved in the theft had drugs stolen twice, making for a total four thefts within a 24 hour period.
'In the 20 years that I've been with Virginia Beach EMS, this has only happened one other time,' Brazle said. 'It's absolutely concerning for two reasons: one, we don't know whose hands this is falling into and it could be a lethal dose of medication that's removed.'
The drug boxes carried by Virginia Beach ambulances are the same ones used by the city's fire department and other ambulance services in Hampton Roads. The boxes contain two dozen different medications, including narcotics.
Brazle said one of the drugs taken this week is morphine, a powerful narcotic.
'Diversion of a narcotic is a very serious issue,' Brazle said.
Because of that, the ambulances from which the drugs were taken had to go out of service to complete exhaustive paperwork and to get new drug boxes.
The drug boxes, which are locked inside a cabinet on an ambulance, can be opened by anyone but cannot be closed in the field.
'The boxes are set up so that if you open it, you can't close it. Only a pharmacist can close it,' Brazle said. 'That's our fail-safe to know someone has tampered with the box.'
Police did not have any suspect information to release as of Tuesday afternoon. Brazle would not rule out the possibility that the drugs were taken by someone inside the EMS organization.
'There are over 70 trucks in the City of Virginia Beach that have these boxes on them so there are literally hundreds of career and volunteer personnel that use them on a daily basis. Anyone who's worked in our system--career or volunteer--in the past several years knows these boxes exist.'
Brazle said the incident has prompted EMS administrators to tighten down on security protocols.
All ambulances are being checked more frequently--including ones not in service.