British police say they have arrested 12 men suspected of plotting a terrorist attack in Britain. The men were taken from different areas around the country as a result of counter-terrorism intelligence work. The country remains on high alert.

Police picked up the men in early morning raids in Birmingham and Stoke-on-Trent in central England, Cardiff in Wales; and, in the capital, London. The men are between the ages of 17 and 24.

John Yates, in charge of terrorism operations for London's Metropolitan police, said, "They were all arrested under the Terrorism Act 2000 on the suspicion of the commission, preparation and instigation of acts of terrorism. They are currently in custody at three separate police stations across the country where they will be interviewed over the coming days."

Yates would not give details, but praised the work of the country's counter-terrorism network in making the arrests. "With the current threat level in the UK at severe, and with the information we had, I believe that today's arrests were absolutely necessary in order to keep the public safe."

Analyst Michael Clarke is the head of the London security research group the Royal United Services Institute. "The body language of the police has been pretty positive. They think they are on to something. The sort of statements they have made, their demeanor, their attitude, they think they have blown something that is really significant. We will see."

Clarke said the threat was not necessarily imminent, but potentially very serious. "The police are very clear that this is the edge of quite a big plot. They have said that this is a large intelligence-led operation, which implies that they have been watching these 12 people for quite a long time, they have decided to move in now. They have obviously decided to move in relatively early. Whatever the plot is, it is not due to come to fruition tomorrow."

He said there is a positive note to the arrests. "The good news, of course, is that if 12 people are involved, it is that much easier for the security services to get some clues and leads on it," said Clarke. "The more people involved, the bigger the conspiracy, the more evidence there is."

Yates called for the public to be vigilant and notify police if they see anything suspicious. "The threat from terrorism in the UK remains real and serious. The threat level remains at severe, which means an attack is highly likely."

Stoke-on-Trent: a city on the River Trent in central England 斯托克（英国中部英格兰斯塔福德郡城市）

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（来源：VOA 编辑：崔旭燕）