A cracker (locally-made hand grenade) was thrown outside the office of the deputy superintendent of police of Gulbaharin Liaquatabadon Saturday afternoon. According to the police, unknown men threw the cracker while they were on a motorcycle. The cracker did not detonate. A bomb disposal squad has been called at the site, said Central SSP ArifAslamRao. Sindh Inspector General of Police (IGP) Mushtaq Ahmed Maharon Saturday sought detailed report from Deputy IGP – West about the incident of cracker attack on office of Deputy Superintendent of Police (DSP). The IGP chief asked the officer to submit a detailed report about actions taken in this regard, informed the spokesman of Sindh Police. According to law enforcement sources, many areas in the Clifton neighbourhood particularly those around foreign diplomatic missions were closed down due to a terror threat. Police sources said a security high alert has been issued for the city’s ‘Red Zone’. Some routes [have been] blocked as part of some extra security measures. Nothing to worry about,” Deputy Inspector General South Javed Akbar Riaz said. The heightened security measures come a month after four militants attempted to storm the Karachi Stock Exchange building.