Seismogram being recorded by a seismograph at the Weston Observatory in Massachusetts, USA. Credit: Wikipedia

A strong earthquake shook Tokyo early Saturday morning, knocking books from shelves, but authorities said there was no risk of a tsunami.

There were no immediate reports of damage or injuries.

The magnitude-5.2 earthquake was 57 kilometers (35 miles) deep and was centered in Tokyo Bay, near Haneda Airport, the Japan Meteorological Agency said. It struck at 5:49 a.m.

Subway and train service was briefly interrupted for safety checks.

The agency warned that the quake could cause following recent heavy rains.