"Mr Warren was well-known to all in our school community and we will be working to support our students and staff and wider Iona family as they come to terms with this tragedy," it stated.
"Mrs Warren will be in everyone's thoughts and prayers," Ms Nimon said.
Eynesbury Senior College in Adelaide paid tribute to its former principal on their Facebook page yesterday afternoon, inviting the community to share their memories of Mr Warren.
"John led and transformed Eynesbury for 7 years at a pivotal time in our history," the post read.
The post detailed numerous qualities the school remembered Mr Warren for, which included being an innovative leader, an intelligent wordsmith, a generous person and a deeply committed and loving husband.
The Ministry of Education deputy secretary for sector enablement and support Katrina Casey said the ministry has sent support by means of advice and guidance to Westmount School (where Mr Warren was East Coast Campus Principal) and Iona College (where Mrs Warren is principal).
"The sudden loss of John Warren is a tragedy and distressing for everyone involved. Our thoughts are with Mr Warren's family, his school and the wider community," she said.
Jon Bowen, the Regional Principal for Westmount School said in a statement last night that: "The staff, student and parent community at Westmount School, East Coast Campus are deeply saddened with the sudden passing of Mr John Warren, Campus Principal."
Mr Bowen said Mr Warren had a very positive impact at our East Coast Campus during his short time there.
"He emanated an infectious desire to connect each student with excellent learning opportunities. John's impact has also been felt nationally through his excellent contribution to school-wide leadership as part of our Senior Education Leadership Team."
" We are very grateful that we had the opportunity to walk alongside John as learners, colleagues and parents. He will be greatly missed as part of the Westmount School community. Our thoughts at this time are with his family."
Hastings District councillor and Sports Hawke's Bay chairman, Damon Harvey, who regularly trains at a Havelock North crossfit gym with Mrs Warren and is a recreational mountain biker, said he was in "complete shock" when he heard the news.
"Last night I heard there was a mountain biking accident and I got a number of texts and calls asking if it was me," he said.
Mr Harvey said he's biked on Te Mata Peak tracks for about 20 years and despite having close calls it's one of his "favourite places in the world".
"I've had more than a few close calls ... but that's part and parcel of mountain biking," he said.
Mr Harvey said while there's always an "element" of risk, he wouldn't class mountain biking as an extreme sport.
"These days tracks are very safe, whereas 20 years ago you probably had a greater risk of incidence," he said.
Mr Harvey extended his deepest sympathies to Mrs Warren and said she was a much-loved member of the community.
"I really feel for her," he said.
