There were explosions at companies in Amsterdam and Kerkrade on Wednesday morning. The Amsterdam explosion happened in the mail room of a company in the Sloterdijk area, the Kerkrade blast happened at a postal company. The police suspect mail bombs. No one was injured in either of the blasts, the Amsterdam and Limburg police said on Twitter.

The explosion in Amsterdam happened in an office building on Bolstoen just before 8:00 a.m. The first emergency call came in just after after 8:00 a.m. At least one ambulance was dispatched to the building in the Sloterdijk area of Amsterdam West ten minutes later.

The Kerkrade explosion happened at a postal company on Wiebachstraat. A suspicious item was first reported to the police at 8:33 a.m., and the police were called out for an explosion at 8:54 a.m. Explosive experts are at the scene to investigate.

"It is as yet unknown whether there is a connection with the explosion of a letter package this morning in Amsterdam," the Limburg police said.

Late in December and early January a series of mail bombs were sent to seven businesses in Amsterdam, Rotterdam, Utrecht and Maastricht. All of them were followed by a threatening letter. Some companies received a letter, but no mail bomb. The bombs were made to look like they were sent by central collections agency CIB.

Because some companies did not realize that the letters were not from the CIB, they mistakenly sent the mail bombs back to the agency. One mail bomb actually reached the CIB, another was intercepted at a mail sorting center in Rotterdam.

None of the previously sent mail bombs exploded. Until Wednesday, the last reported mail bomb was on January 10th.