A 13 year old boy was left in critical condition after a stabbing near a school in Hamburg on Monday, with police detaining two teenage suspects following a large scale search operation.

Thousands of students across Germany staged protests on Friday against a new military service law that mandates health screenings and questionnaires for 18-year-old men.

A massive fire has broken out in the city of Hamburg, Germany, causing explosions and scattering debris. Images shared online show thick grey plumes of smoke rising above the city's skyline.

Two of Germany's largest police trade unions have called for increased video surveillance and additional personnel following a knife attack at Hamburg Central Station on Friday, in which a woman injured 18 people.

Several people have suffered life-threatening injuries in a knife attack at the main railway station in the German city of Hamburg, police have said.

Germany's Munich and Hamburg airports were hit by strikes by public sector union Verdi on Thursday and Friday, with airlines cancelling about 80% of flights in Munich.

More than 12 people were injured, most of them lightly, in a collision between a long-distance train and a semi-truck in a suburb of the northern German city of Hamburg on Tuesday.