The ABC head office is in security lockdown after receiving threats over Zaky Mallah's appearance on Q&A

Zaky Mallah on Q&A. Source: screenshot

The ABC offices in Sydney are operating on security lockdown protocols after threatening phone calls in relation to acquitted terror suspect Zaky Mallah’s appearance on its Q&A program.

An ABC spokesperson told Business Insider that it had received more than 1000 phone calls about the Q&A issue this week.

“Security has been stepped up at major ABC offices across Australia as a precautionary measure to protect the welfare of staff. There have been a number of threatening phone calls,” the spokesperson said.

The lockdown means the public, who often used the two entrances into the Ultimo building as a shortcut between Harris Street and Central train station, are unable to enter the building without permission.

While the ABC has apologised for Mallah’s appearance on live television, communications minister Malcolm Turnbull has ordered a departmental investigation into the incident.

Overnight, ABC managing director Mark Scott launched a staunch defence of his organisation during a speech at the Centre for Corporate Public Affairs.

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