Rescue efforts continue after strong earthquake in south-west Japan

Emergency services and rescue teams are continuing to help people following a strong earthquake in south-west Japan.

The 7.1 magnitude quake struck Kyushu, one of Japan's main islands, at 16:27 local time on Tuesday (7:27am UK time), damaging buildings, roads and bridges.

A magnitude 7.1 earthquake is considered very strong and can cause serious damage, especially near its epicentre, which is the point on the Earth's surface directly above where the earthquake begins underground.

Thousands of people have been moved from their homes to safety, and are staying in emergency shelters.

Officials said nearly 5,000 emergency services workers - including firefighters and police officers - have been sent to the area to help with the rescue efforts.

They are helping those affected by the quake, including at a large and popular shopping mall which partially collapsed.

Historic sites in the area were also damaged, including the worship hall of the 19th Century Yatshushiro Shrine and the walls of Kumamoto Castle, which both collapsed.

Footage from Japan's national broadcaster NHK, showed cracked roads and bridges.

Special evacuation centres have been set up, proving people affected by the earthquake with food, water, air-conditioning and power generators.

Officials say that 13 people have died.

After the main earthquake there have been smaller quakes, called aftershocks.

These can happen after a big earthquake and may cause more damage, so people are often told to stay away from unsafe buildings.

Japan's Chief Cabinet Secretary, Minoru Kihara, urged people to stay calm.

"We urge residents in areas where the shaking was particularly severe to pay close attention to evacuation information issued by local authorities via radio, television and the internet," he said.

Japan has many earthquakes because it sits on the Pacific Ring of Fire. This is an area around the Pacific Ocean where several of Earth's plates meet and move.

The Ring of Fire refers to a string of earthquake sites, volcanoes and tectonic plates around the Pacific.

It spreads across around 25,000 miles from the southern tip of South America all the way to New Zealand.

Tectonic plates, huge slabs of the Earth's crust, are not fixed but are constantly move on top a of layer of solid and molten rock.

When these pieces move they can cause earthquakes or volcanoes, or both.

Roughly 90% of all earthquakes occur along this area and the ring is dotted with 75% of all active volcanoes on Earth - that's 452 individual active volcanoes.