Law enforcement personnel on Thursday scaled up security measures and sealed some areas and roads, particularly those surrounding foreign diplomatic missions, in Karachi's Clifton neighbourhood reportedly due to some terror threats, officials and witnesses said.

The blockade of residential areas and routes caused inconvenience to the area's residents and commuters.

Police sources said that in view of a possible terrorist attempt, a security high alert has been issued for the city's 'Red Zone', particularly where foreign consulates and residences of their staff are located in Clifton.

Some of the residents while talking to Dawn said that for the last two months, they have been witnessing more security specifically in Clifton's Block-4 near Abdullah Shah Ghazi's mausoleum where some consulates including that of China, up-scale restaurants frequented by foreigners and a number of art galleries are located.

But on Thursday, they said, the situation appeared to be quite serious as a major part of Clifton Block-4 was sealed by erecting temporary barriers that prevented the movement of vehicles.

Police were also searching vehicles and stopping people in the area for checks.

Authorities were tight-lipped about any specific threats or a perception of the same. When contacted, Deputy Inspector General South Javed Akbar Riaz said: “Some routes [have been] blocked as part of some extra security measures. Nothing to worry.”

Commissioner Karachi Iftikhar Ali Shallwani, meanwhile, said that “It’s a routine alert against any imminent threat by LEAs.”

Some areas near Abdullah Shah Ghazi's mausoleum were already sealed for 15 days because of an increase in coronavirus cases and these restrictions were lifted on Wednesday.

The development comes less than a month after four heavily armed militants attempted to storm the Pakistan Stock Exchange located in Karachi's high-security zone. All four terrorists were killed in the gun-and-grenade attack that also claimed the lives of four security personnel.

The outlawed Balochistan Liberation Army (BLA) had claimed responsibility through social media, but such an attack reflecting “frustration” of Indian intelligence agency RAW over peace in Pakistan’s financial hub was not possible without the help of any foreign hostile agency, the chief of paramilitary Rangers had told a press conference after the attack.

In November 2018, a terror attack targeting the Chinese consulate in Karachi was foiled by security forces. The attack had left at least seven people dead.