India, Sept. 8 -- Hours after a section of a terminal at London's Heathrow Airport was evacuated and temporarily closed due to a "possible hazardous materials incident", the airport said that its Terminal 4 "was safe to reopen".

"Emergency services have confirmed Terminal 4 is safe to reopen and we are doing everything we can to ensure all flights to depart as planned today," the operator of UK's main international airport wrote on social media.

"We are very sorry for the disruption caused, the safety and security of our passengers and colleagues is our number one priority," the airport added.

The London Fire Brigade announced it was withdrawing its operations roughly three hours after being alerted to a "possible hazardous materials i...