People from across central and southern England have reported an earth tremor.
The BBC has received calls from people in Staffordshire, Warwickshire, Leicestershire, Berkshire and the West Midlands reporting an "earthquake".
The tremor could be felt in central Birmingham at about 0100 GMT but it is unclear if it has caused any damage.
The West Midlands was hit by an earthquake in 2002 in the Dudley area that reached 5.0 on the Richter scale and caused damage to homes.