Security camera footage showed a bright comet fragment lighting up the sky over the Portuguese city of Braga on Saturday night (May 18).

The astronomical phenomenon was visible in various parts of Spain in Portugal.

On Sunday (May 19) morning, the European Space Agency (ESA) shared on X a video captured by its "fireball camera" of what it described as a "stunning meteor" over the skies of the western Spanish city of Caceres, near the Portuguese border.

But it later said it appeared to be a "small piece of a comet" and not a meteor, estimating it flew over Spain and Portugal at a speed of 45 km (28 miles) per second before burning up over the Atlantic.

"The likelihood of any meteorites being found is very low," the ESA said.

In both countries, videos shot in several cities and towns went viral on social media, showing the object crossing the night sky at high speed and illuminating it in bright tones of blue and green.

The Spanish Calar Alto astronomical observatory also said a preliminary analysis by Andalusia's Institute of Astrophysics revealed the object had a "cometary origin."

Many contacted emergency services to report what happened. A spokesperson for the Spanish Emergency service 112, in Madrid, told Europa Press news agency it had received several calls.

(Production: Monica Naime, Jose Pablo Diaz)