OAK BLUFFS — One clumsy ferry passenger made a mistake that would trigger a 14-day police operation.

The man dropped his bag. Security looked inside. What they found would lead to four arrests, a 90mph highway chase, and nearly a pound of cocaine seized.

It all started in a parking lot two weeks earlier.

Late on the night of February 21, an Oak Bluffs police officer spotted a black Dodge Charger parked at Medeiros Cove with two people inside.

Something didn't look right.

The officer approached. Inside, he spotted what looked like drug paraphernalia in plain view. A search turned up 8.4 grams of cocaine, packaged for distribution.

Douglas Da Silva, 24, of Edgartown, was arrested. At the time, it seemed like a routine bust.

But investigators were just getting started.

Ten days later, Steamship Authority security made a call that would crack the case wide open.

A passenger had dropped a bag on a ferry heading to Martha's Vineyard. When security picked it up, they immediately knew what they were looking at.

Cocaine. 18 grams of it. Individually packaged. Ready for distribution.

Task force detectives rushed to the Vineyard Haven terminal with Tisbury Police. They boarded the ferry and found their man: Adrian Junior Rodrigues Dos Santos, 19, of East Falmouth.

Officers escorted him off the boat. A records check revealed he was already wanted on an outstanding warrant from another jurisdiction.

He's been sitting in the Dukes County Jail ever since.

The ferry bust gave investigators the break they needed. Two days later, on March 5, the Martha's Vineyard Drug Task Force obtained a search warrant and tracked a target vehicle onto Route 28 in Falmouth.

A uniformed Falmouth officer spotted the car. The driver was flying — more than 90 mph down the highway.

The officer pulled them over. Both occupants were detained on the spot.

Then came the search.

Inside the vehicle: 407.85 grams of cocaine — nearly a full pound — along with pills and drug paraphernalia. The Barnstable County Sheriff's K9 Unit assisted in the recovery.

Keslley Luiz Xavier, 32, and Mateus Souza de Oliveira, 33, both of Edgartown, were arrested and charged with trafficking in cocaine (200 grams or more) and conspiracy to violate drug law.

Bail was set at $10,000 each. Both men were transported to the Barnstable County Correctional Complex.

In just 14 days, what authorities described as a coordinated multi-agency operation resulted in four arrests and 434 grams of cocaine seized — just under a full pound.

The Martha's Vineyard Drug Task Force led the operation, working alongside the DEA Cape Cod Regional Office, Oak Bluffs Police, Falmouth Police, Tisbury Police, and the Barnstable County Sheriff's Office.

"The Falmouth Police Department appreciates the effective leadership and collaboration of the Oak Bluffs Police Department and the DEA Cape Cod Task Force in this investigation and remains committed to ensuring the safety of our community," Falmouth PD said in a statement.

All four defendants are presumed innocent until proven guilty in a court of law.