Two men found to have conducted illegal land clearing detained a man for 30 minutes when he came to serve them legal documents, a court has heard.

Dr Mustapha Kara-Ali and Diaa Kara-Ali were found to have conducted illegal land clearing and other development on a rural property at Colo, in Sydney's north west.

Key points: Mustapha and Diaa Kara-Ali are being pursued for contempt of court after allegedly continuing to illegally build on a Colo property

Mustapha and Diaa Kara-Ali are being pursued for contempt of court after allegedly continuing to illegally build on a Colo property Mustapha is the Imam of a religious guild based on the property and claims they are exempt from Australian law

Mustapha is the Imam of a religious guild based on the property and claims they are exempt from Australian law A man serving court papers claims he was detained on the property for 30 minutes

Dr Kara-Ali runs a religious guild called Diwan Al Dawla on the property and claims they are exempt from Australian law because all of the work has been done in his role as Imam of the guild, which is classed as a basic religious charity.

This claim is not supported by the Australian Charities and Not-For-Profits Commission.

Neither men have taken part in the court proceedings so far.

Last month, the Land and Environment court set out a series of orders for the men to remove movable buildings, fences and a boat ramp, as well as prepare a revegetation plan for the areas they had cleared.

Land and Environment Court ruled the property had been illegally cleared and ordered movable buildings be removed. ( Supplied: NSW Courts )

The first deadline passed on Monday and Hawkesbury City Council is now pursuing contempt of court charges, telling the court the men were continuing to build on the property.

Man delivering court documents 'padlocked inside gates to property'

Affadavits filed to the court today, detailed an incident in which a man delivering court documents to the Kara-Alis was locked inside the Colo property.

The affidavit of Frank Hoare, a process server, claimed he was approached by Diaa and Mustapha Kara-Ali on the property.

"Get off this sacred land. You are an infidel, a man of the cross and a thief," one of the men told him, according to the affidavit.

The Kara-Alis told Mr Hoare to take the documents with him, before Mustapha Kara-Ali padlocked the front gate before he had time to leave, the affidavit alleged.

It claimed Mr Hoare sat in his car while Diaa Kara-Ali rode a horse in another paddock and Mustapha Kara-Ali walked to the end of the property and prayed.

"I did not have any reception on my mobile phone," the affidavit stated.

"I honked my horn to passing traffic to no avail.

Before and after photos show the loss of vegetation after the men cleared the block. ( Supplied )

"I continued to sit in my car and ... [Diaa] kept riding his horse around the paddock, which would be described as an intimidatory [sic] manner."

Mr Hoare said Diaa Kara-Ali rode up to the car, while an elderly man threw the papers in the front seat.

The affidavit said the Kara-Ali's eventually unlocked the gate and Mr Hoare drove out, leaving the court documents in front of the gate.

Mustapha Kara-Ali told the ABC he would not take part in the court process because he did not believe it to be a secular institution.

"This is religious persecution par excellence," he said.

"We have our religion and the cross bearers have theirs."

Another affidavit claimed that in a separate visit to the property to serve documents, Diaa Kara-Ali took the documents, threw them on the ground and stomped, jumped and spat on them.

"I will bury these like I will your cross in the name of Muhammed," Diaa Kara-Ali allegedly said.

"Mustapha Kara-Ali ... started to film me and the police officers saying, 'Look at this abuse' and 'You fucking dog, you Christian crusader, your cross will be buried like you'."

Justice Terry Sheahan told the court he would direct Diaa and Mustapha Kara-Ali to attend the next hearing later this month.