Police allege he climbed through a hole in a fence at Avalon Airport, near Geelong, before making his way on foot to the aircraft about 2.20pm.

About 160 passengers were on board the Jetstar plane, which was due to fly to Sydney.

Appearing via video link in a children’s court hearing today, the teen’s identity remains undisclosed due to legal restrictions, while his lawyer requested a further postponement.

The lawyer told the court the boy had undergone scans of his brain at a regional hospital and was due to have further scans in late August.

Doctors were assessing whether he had an “organic or physiological neurological condition”, the lawyer said.

The lawyer also mentioned that a psychological evaluation is scheduled for later this week. However, the psychiatrist indicated that a report would only be available once the scans are finalized.

The magistrate allowed the case to be adjourned to October so the medical material could be obtained.

Prosecutors also successfully applied to withdraw four charges, including allegations the boy stole two 12-gauge shotguns and possessed a long arm firearm without a licence.

The teen is still facing charges including boarding a commercial aircraft while in possession of a firearm and making threats that he had a bomb in his bag.

During a March hearing, it was revealed a joint counter-terrorism taskforce was investigating the Avalon Airport incident and the boy may have communicated with a foreigner or foreign entity.

Federal police successfully obtained a suppression on the identity of the foreigners, as well as the nature or content of the boy’s communications.

The nature or contents of documents allegedly found in the accused’s vehicle have also been suppressed.

The magistrate today extended those suppressions to the next October court date.