Specialist police have joined the search for a Belgian backpacker, missing on the New South Wales north coast, as authorities examine a bushy headland near Byron Bay’s famous lighthouse.

Theo Hayez, 18, was last seen leaving the holiday town’s Cheeky Monkey’s bar about 11pm on 31 May.

Dozens of people, including State Emergency Service volunteers and members of the public, on Tuesday returned to the area around Cape Byron Lighthouse where the last “ping” from Theo’s phone was recorded on 1 June.

CCTV footage of missing Belgian backpacker Theo Hayez (right) in a Byron Bay bottle shop the night he disappeared. Photograph: AFP/Getty Images

The search was suspended on Tuesday evening with nothing of interest found, NSW police said in a statement.

It resumed at 11am on Wednesday with specialist police forces again focused on the lighthouse and Tallow Beach.

Theo’s distraught father Laurent made an emotional plea for help on Monday, begging encrypted chat service WhatsApp to grant police access to his son’s final known conversations.

The company has provided what information they can but are unable to access the content of the messages.

Belgian police are also working in Europe to speak with people Theo may have contacted in his final known hours.

Theo Hayez was last seen about 11pm on 31 May. Photograph: Facebook / Theo Hayez

More than $68,000 has been raised via a GoFundMe page for the Hayez family, part of which was used to help Laurent Hayez fly to Australia.

Laurent Hayez arrived in the country late last week and has vowed to stay until his son is found.