The organisers of the London Marathon say they "fully expect" it to go ahead as planned on Sunday, although "security will be reviewed", after two explosions hit the Boston Marathon yesterday, although "security will be reviewed."
Vale of Glamorgan MP Alun Cairns is among the Welsh runners taking part, and has urged others to "turn out in confidence."
As a runner in Sunday's #LondonMarathon I hope all athletes & spectators turn out in confidence & defy the terrible acts in Boston
More top news
Whilst it should be drier than Wednesday, some rain is still expected.
It will stay largely cloudy tonight and there will be some further rain around, with central parts perhaps staying driest.
ITV Wales understands the reason for the inquiry call stems from concerns raised at the end of 2016 over a former healthcare support worker.