The Royal Newfoundland Constabulary is investigating three armed robberies in St. John's early Saturday morning that police say may be connected.

Four people — three men and one woman — were arrested in connection with one of the three robberies.

Around 2:30 a.m., police and the K-9 unit responded to the first robbery at the Subway restaurant in Mount Pearl.

The RNC said three masked people got away with an undisclosed amount of money, and fled on foot.

About 20 minutes later, two suspects held up a Tim Hortons on Portugal Cove Road in the city's east end and left with cash.

Police said the third incident happened around five minutes after the second robbery, at the Ultramar gas station on Elizabeth Avenue.

However, the RNC apprehended four individuals just after they left the scene.

They were held for a court appearance Saturday.

Police said they may be responsible for all three incidents.

No injuries were reported, and the RNC investigation is ongoing.