Dutch police arrested a 20-year-old man from Amsterdam on Tuesday in connection with several bomb attacks in Germany.

The man allegedly headed a gang involved in “attacks to order” in and around Frankfurt last summer, for which he recruited teenagers as young as 13. A woman and four men were also arrested, aged between 18 and 24.

According to German media, the arrest was “well-timed” because Friday sees the start of the trial against a 15-year-old who set fire to a bar in Frankfurt for €3,000. He too was allegedly recruited via Snapchat by the man from Amsterdam.

The investigation started after a spate of explosions in Taunustein, near Frankfurt, and in Frankfurt itself.

The German police traced the attacks to the 20-year-old and issued a request for his arrest. Subsequent searches at his address and those of the other suspects turned up two guns, ammunition, several devices and drugs.

The suspect is thought to have told the attackers how to make bombs and to have monitored the attacks closely. He is currently in custody in the Netherlands until his extradition to Germany.