Police raided an alleged 'bomb-making factory' in Birmingham last night as five men were arrested on suspicion of terror offences.

After one of the arrests near central Birmingham, an army bomb disposal team was called to the scene.

Searches were ongoing last night at a number of properties in Stoke and Birmingham.

Police said the arrests were part of an intelligence-led investigation that was still on-going.

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A bomb disposal squad (pictured) arrived at an address in the Lee Bank area of Birmingham

The bomb disposal team was called to a property in Birmingham as five men were arrested by counter terrorism police

The Bomb Disposal Squad was photographed outside an address on Florence Street, Birmingham

Two of the men, aged 32 and 37, were arrested in the Stoke area of Staffordshire while another two, aged 18 and 24, were arrested at their home addresses in Birmingham.

Another man, 28, was arrested at a different location in Birmingham.

Staff and guests at the Pentahotel, which is on the edge of a police cordon, were advised to stay inside as a precautionary measure.

Veshh Kumar, a concierge at the hotel, said: 'We had seen police activity since about 12.00pm then all of a sudden at about 4pm the bomb squad and the army arrived.

'The police told us to keep all the guests safe indoors. We don't know which building it was or what has taken place.'

One resident, who lives in nearby Bishopgate Street, added: 'Bath Row is cordoned off at the moment.

'There are about seven police vans and i would estimate over 35 police officers.

'The bomb disposal unit is there and I have seen a white bomb disposal robot. There is also an ambulance and two fire engines.

'I have never seen a police operation like this in my life.

A member of the forensic team was seen outside the property on the street in Birmingham

Counter terrorism police arrested three men, aged between 18 and 28, in Birmingham today (pictured)

'An officer told me it was a counter-terrorism operation and it is scary to think something like this is happening on the street next to mine.

'However it is reassuring to see police responding in this way with such a huge response.'

West Midlands last night refused to comment on claims that it was bomb making factory was raided.

But a security source told The Times that the raid was on a bomb-making factory and a significant step forward in a long-running investigation involving M15 and the West Midlands counterterrorism unit.

He told the paper that police and the bomb squad were searching one property that police suspected was being used to make home-made bombs.

The West Midlands fire service tweeted: 'Fire crews have been supporting police colleagues with an ongoing operation in the Lea Bank area of #Birmingham.'

Police sealed off the road in Birmingham (pictured) after making an arrest on Friday

The five arrested men are all being held by counter terrorism detectives in the West Midlands

The Army Bomb Disposal Team was called to the Lee Bank area of Birmingham as a precaution

The alleged plot could be the most significant since Tarik Hassane and Suhaib Majeed were jailed in 2014 for planning a drive-by attack on police officers and soldiers in central London. They were jailed for life in April.

In April this year police arrested five people in connection with terror offences in Birmingham and at Gatwick airport which were reportedly linked to attacks on Brussels and Paris.

The most recent bomb plot in the UK was led by Mohammed Rehman and Sana Ahmed-Khan, a husband and wife from Reading, who were planning an attack in central London in June last year.