According to the IPMA, the earthquake struck at 5:11 a.m. local time (6:11 a.m. CET) and had an epicentre 58 kilometres west of Sines, on the high seas, at a depth of 21 kilometres.

“We received a large number of calls, mostly from people who wanted to know what was going on and what they should do. At this time (6:00 a.m. local time), we have yet to count the number of calls received,” stated Commander José Miranda of the National Emergency and Civil Protection Authority (ANEPC).

Miranda stated that there are currently no reports of victims or substantial damage.

“We only have information at this time about a situation in a street in Sesimbra in which possible cracks in buildings are being assessed,” a spokesperson said.

In a statement released Monday morning, the Portuguese government stated that it was “in close coordination with all relevant services” following the earthquake.

It informed the public that there was no evidence of personal or property damage and urged them to remain calm and follow the National Emergency and Civil Protection Authority’s advice.

The tremor was not powerful enough to cause a tsunami on the US East Coast or Europe.

More than 2,000 people used the United States Geological Survey’s (USGS) “Did you feel it?” tool to report the earthquake on Monday.

“We are on the ground level flat, and the entire building shook above us, and the floor underneath us felt like it was sinking. “Our dogs woke up and were freaked out,” Keira McCann told BNO News. “We did not expect to experience this in Portugal.”

Vera Fassbender, who resides in Lisbon, also stated that she “felt it shaking for 3-5 seconds”.

“I am on the eighth floor. It was a minor shaking, but extremely noticeable and a little frightening!”

The earthquake was felt throughout Morocco, including Casablanca.

“Initially thought I was just shaking while sleeping until my brother rushed to properly wake me up and tell me that he felt it too,” Rimah Oubella in Casablanca stated.

According to the USGS, no earthquakes have occurred within 400 km of today’s epicentre in the past 30 days.

While there has been little recent seismic activity, Portugal, particularly its southern portion and the Azores, is located near the boundary between the Eurasian and African tectonic plates. This placement puts the area vulnerable to seismic activity, including earthquakes.

Each year, the country encounters several mild earthquakes with a magnitude of less than 3.0, which are not felt by the inhabitants or cause any damage.

Earthquakes with magnitudes ranging from 3.0 to 5.0 are less common, but they do occur on a regular basis. People can feel these, and they may do mild injury.