Sir Michael was giving evidence to MPs on the education select committee.
He said inspectors had found governors had over-stepped their role and heads were "intimidated and undermined".
Ofsted had inspected schools in Birmingham in the wake of claims of take-overs by Muslim hardliners.
Sir Michael said inspectors were "looking at other schools where this might be a problem. We've certainly been to schools in Bradford and Luton".
.... He also explained how previous inspections did not raise concerns about school take-overs or extremism.
"It's possible to miss these issues. Particularly if head teachers are frightened, if school leaders are frightened, if teachers are frightened to speak out because of fear for their jobs, fear they won't be promoted."
Sir Michael said he had spoken to parents in Birmingham and had been "hugely impressed" by them.
"We need to get this sorted as soon as possible," he said. [BBC] Read more
