Security at the famous Saibaba shrine in Shirdi has been beefed up after the temple authorities received a letter threatening to trigger a blast on November 9 as also the Thakcerays' house in Mumbai, police said on Wednesday.

"The anonymous letter, written in Hindi, has also threatened to set off explosions on the same day at a local Shiv Sena office, Shiv Sena Bhavan at Dadar in Mumbai, the residence of Thackerays, 'Matoshree', the place of cremation of Bal Thackeray on Shivaji Park ground in Mumbai, besides famous Khajrana Ganesh temple in Indore," acting Executive Officer of Shirdi Trust Ajay More said.