On Tuesday evening, there were two tremors felt by residents of Marratxi and Santa Maria del Camí which are as yet unexplained.
The National Seismological Centre has not reported any significant earthquake activity, the tremors having occurred roughly two hours apart - 7.40pm and 9.40pm.
Rather than tremors, there were reports of explosions. The mayor of Santa Maria, Nicolau Canyelles, says that a large explosion was heard. The police were unable to find any focus for this. "We are in the dark."
Residents report chairs and tables having been moved. "Everyone went out into the street to see what was happening and for fear that roofs might collapse."
There have also been reports of a "very strange smell". No damage, as such, has been reported.