German police have arrested five Tajik nationals on suspicion that they were members of an Islamic State (IS) terror group cell that had been planning attacks on US forces stationed in Germany, prosecutors said Wednesday, according to Agence France-Presse (AFP).

Four of the suspects were reportedly arrested after dawn raids on Wednesday targeting several apartments and six other locations in the western state of North Rhine-Westphalia.  Another Tajik national was previously detained.

The five were also allegedly planning attacks on individuals they deemed critical of Islam, prosecutors in the city of Karlsruhe said.

The suspects -- named as Azizjon B., Muhammadali G., Farhodshoh K., Sunatulloh K. and Ravsan B. -- are accused of joining the Islamic State terror group in January 2019 and initially planning to carry out attacks in Tajikistan.

They then switched their focus to Germany after receiving instructions from two high-ranking IS leaders in Syria and Afghanistan, prosecutors said.

The five men had been planning to attack targets including US air bases and had already ordered bomb parts online, as well as stocking up on firearms and ammunition.

They reportedly also planned an assassination attempt on a person they believed had expressed Islam-critical views in public, and had already begun spying on the intended victim, prosecutors said.

Two of the suspects are also accused of travelling to Albania to carry out an assassination attempt in exchange for 40,000 U.S. dollars. However, the project failed and they returned to Germany.