More than 2500 students and parents were caught in chaos as students attempted to sit the NSW selective schools and Opportunity Class (OC) tests today.

Students and their parents were stuck for hours at the Canterbury Park Racecourse grounds, waiting for their scheduled test.

Public order and riot squad police were called in to help control the chaos, with hundreds of students blocking the entrance to the venue.

There were two exams scheduled at the venue today, one at 8am and another at 12pm.

Parents told 9News it was “chaos” as they arrived this morning.

“There was absolutely no signage, where to line up or anything,” one woman said.

The first exam was scheduled to finish at 11am.

Parents told 9News they were told at 10.55am that the test would be delayed by an hour.

9News understands a combination of technological issues, and logistical problems resulting from this morning’s delays on the M1 motorway contributed to the delays.

One parent told 2GB radio that students were unable to connect to the wi-fi in the testing centre.

The waiting crowd became restless, with some parents calling police to help control the chaos.

The riot squad soon arrived on site.

“There was no one to control the crowd, and without someone to control the crowd, you’re not going to get results, so that’s why I called the police,” one parent, who wanted to remain anonymous, told 9news.

About 1.30pm, 90 minutes after the second exam was scheduled, the children who were waiting to take the second exam were told that it had been cancelled.

“Just tell me one thing, how hard is it to organise this when we can organise the Olympics, Commonwealth games?” one furious parent said.

“We’ve got the Olympics coming up, how are we going to organise that when we can’t even organise one like this.”

The education minister’s office told 9News they concede the issues should not have happened and will be conducting a review into what went wrong.

“My sincere apologies to the families and students who turned up today for what is an important day in their lives,” Education Minister Prue Car said.

“Taking an exam is stressful enough as it is and this isn’t good enough.

“I have asked the Department of Education for an urgent review and it is working quickly to address the situation.”

Further tests that were planned for this weekend at Randwick, Homebush and Canterbury have been postponed, with the Department of Education apologising for the inconvenience.

“I apologise for the inconvenience and stress caused to students, parents, and carers as a result of these major disruptions,” NSW Department of Education Secretary Murat Dizdar said.

“What occurred was unacceptable and fell well short of the department’s expectations.

“I understand the frustration of families who had made arrangements to attend the tests.

“Due to concerns regarding crowd control at the large three test centres at Randwick, Homebush and Canterbury, further scheduled tests to be held at these sites tomorrow and Sunday have been postponed.

“Testing will go ahead as planned at the other 104 testing sites across the state.

“I want parents and carers to know that we are committed to rectifying this situation.

“The department will be in direct contact with a range of options for make-up tests.”