An alert has been sounded in Meerut zone after police received a letter, purportedly by al-Qaeda, threatening a series of blasts in trains and major railway stations of western Uttar Pradesh.

Security had been tightened and a general alert sounded, especially on trains and railway stations in Meerut, Bareilly, Muzaffarnagar, Saharanpur and Ghaziabad after the receipt of a letter, claimed to be sent by al-Qaeda, Inspector-General of Police N B Singh said on Sunday.

"The letter might be a fake one but the police cannot ignore it," he said. The letter was received by the Muzaffarnagar police two days ago and immediately brought to the notice of state Home Secretary Alok Sinha, who directed senior police officials of the zone to ensure security in trains and railway stations.

The letter had mentioned Meerut and Bareilly stations but had not named any specific trains. The IGP added the public had been advised not to touch any objects found lying around in trains, buses, public parks and markets.

The state capital went into a tizzy a few days ahead of former American president Bill Clinton's visit in early September after an al-Qaeda letter claimed to have planted mines and explosives at Charbagh railway station and other sites. The letter turned out to be a hoax.

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