National School

Keon Richards, 38, who works for the national school meals programme, was last seen leaving work on 26 February.

The National School Dog Alliance, which also gives school dog advice, said it was important the right breeds were used and that they were properly trained.

The last confirmed sighting of Ms Lynch was outside a national school about 400 yards from a bridge over the canal where she was found 30 hours later.

A key question in the case is whether Ms Lynch walked off on her own from the national school towards the bridge.

In recent weeks, Trump has floated the idea of a national “school choice” policy.