Four missions of Western nations have received threats by suspected Islamist militant organistions, prompting Bangladesh government to considerably hike security arrangements.
Those targeted are the US, Britain, Canada and Australia, media reports said.
Unnamed officials spoke of a demand $100,000 and for the release of Mas Selamat Kastari, "German bomb engineer" detained in Johor, Malaysia, on Friday.
They also demanded that the embassies shut down their activities within seven days otherwise they would carry out attacks against them.
Security was beefed up at Baridhara-Gulshan in the national capital's diplomatic zone located downtown after militants late Thursday night issued threats to blow up four embassies.
Dhaka Metropolitan Police (DMP) Commissioner A.K.M. Shahidul Huq told The Daily Star: "Unknown criminals sent faxes to the embassies of USA, Canada, Britain and Australia threatening to blow them up."
"They claimed to be Jemaah Islamiyah al-Qaeda but we are not sure whether there is any such organisation."
"Following this, we held separate coordination meetings with those embassies," the DMP commissioner said.
"Security measures have been beefed up with the deployment of additional forces, increased intelligence vigilance and setting up of police check posts."
Officer-in-charge of Gulshan Police Station Kamrul Alam Mollah said they have increased the number police check posts to avert any subversive acts.