A Greenwich student is one of four men being questioned by counter-terror police on suspicion of being involved in a potentially "significant" Islamist terrorism plot, according to reports.

One of them, Gusai Abuzeid, 21, a student at the Greenwich School of Management and part-time Primark worker, was arrested at home in central London, according to the Daily Mail. 

His brother told the paper his sibling was not religious and could not be involved in an Islamist plot.

The men, aged 20 to 21, were arrested yesterday in a series of raids at addresses across London, during which one suspect was Tasered by police.

At least one of the suspects is believed to have travelled to Syria and one line of inquiry is to establish any possible links with Islamic State (IS), the extremist group behind the beheading of British aid worker Alan Henning.

Counter-terror officers believe the raids were an "early disruption" of what could have turned into a "significant plot".

Commenting on the arrests, Metropolitan Police commissioner Sir Bernard Hogan-Howe said: " It is one of a series of arrests that we have had over the last few weeks which, taken together, for me confirm that the drumbeat around terrorism has changed. 

"It's a more intense drumbeat - we are having to be more interventionist and a lot of it is linked back to Syria and Iraq."