A magnitude 6.0 earthquake has struck off the coast of Japan where the Tokyo Olympics 2020 are being held.
While there have been reports of some athletes and journalists feeling the force of the earthquake there are said to be no concerns over a tsunami.
The quake struck at a depth of over 6 miles about 75 miles east-northeast of the Japanese town of Hasaki, which is some 75 miles east of Tokyo.
The US Geological Survey reported other earthquakes — ranging from magnitudes 4.1 to 5.1 —had occurred in the same area off the Japanese coast.
At the Park Hotel in central Tokyo, a giant tower which is part of the media city over Shiodome station, visitors are informed that the building might shake if there is a quake.
UN NERV, who posts disaster warnings for Japan, said: "At around 5:42am, an earthquake with a magnitude of 5.6 occurred offshore Ibaraki Prefecture at a depth of 30km.
"The maximum intensity was 2. There is no threat of a tsunami."
Foreign journalists covering the games in Tokyo took to social media after tremors were felt in the city.
An international correspondent with CNN said on social media: "Earthquake in Tokyo right now. I’ve felt the shaking for about 30 seconds. Still going."
Another journalist with NBC said: "I felt what appeared to be a mild earthquake here in Tokyo. Around 5:33 am Wednesday morning here.
"Rolled for a good 20 seconds. Interestingly my crew 3 floors below me felt nothing. Japanese meteorological agency reporting 6.0 magnitude."
Mark Beretta, an Australian journalist, described the feeling of an aftershock while live on air.
"I thought that I was having a Twisties gymnastics moment," he said. "The lights were moving. I just noticed the roof started moving.
"People around Tokyo were trying to work out what had happened. It is unusual for a visitor."
A spokesperson at Sunrise, the show he was hosting at the time, wrote on Twitter: "Welcome back to the Olympic city where we are currently in an earthquake."
"Mark Beretta just powered through his sports report while Tokyo was being hit by a tremor."
The quake, which struck around 5:30am local time on Wednesday, had an epicentre about 40 kilometers (25 miles) from land, deep off the coast of Japan, according to preliminary reports.
The quake first occurred more than 6 miles deep in the waters near the town of Hasaki, which is about 75 miles east of Tokyo, according to the US Geological Survey.
Japan is situated in a seismically active zone known as the 'Ring of Fire' and regularly sees the full force of powerful earthquakes.
In 2011 a 9.0 magnitude earthquake and the tsunami that followed killed thousands of people and caused the Fukushima nuclear plant disaster.
