A cross the year14 per cent of those arrested on suspicion of terror offences were female, the largest proportion on record and most arrested were over 30.
There were increases in arrests across all ethnic groups but this was particularly significant in arrests of white people, which increased by 92 per cent compared to the previous year - 127 compared to 66 arrests.
Overall, 34 per cent of those arrested on terror-related offences were white compared to 29 per cent in 2016. 70 per cent considered themselves to be British.
M ost people charged with terror offences serve between four and 10 years in prison but last year showed a decrease in those serving life - down from seven people to two.
As of June this year 204 people were in custody for terror-related offences, an increase of 35 per cent and continuing an upward trend seen since the statistics were first collected in 2001.
T he majority of terror prisoners held Islamist extremist views, 91 per cent, while five per cent held far-right views and four per cent classified as other ideologies.
A Downing Street spokesman said: “The Prime Minister has said after the appalling terrorist attacks that took place in this country in Manchester and in London that the threat from terrorism is severe and that it is changing and that continued hard work is required to tackle this threat.
“Police and security services are working incredibly hard and I think these figures reflect both the threat and the efforts that the police and security services are putting into dealing with them.”
Read more news of London on our site.