Is it away to explode?

Next door isn't in at the minute and I don't have contact details to tell anyone.

All yesterday the pipes between ours and theirs clonked and we weren't sure whose pipes it was, ours or theirs. Now there's clonking again and boiling water is streaming out of a pipe just under the gutter every few minutes at the opposite side from the boiler, or where our boiler is.
The roof is the attic, no half stories.

Any ideas and will something in there be going skewiff?

We need a random questions and a random comments thread.

Plastic we think, but it's pained to match. They have gas, on the same side of the building but the other end of the house.
That's what we thought was happening. They've been out for a while. Thankfully it's cold, but only a light frost. So I hope it's boiling over rather than the pipes bursting inside.

Husband knows someone who was called to a fire, the house had been sold to a local property seller. They didn't drain the pipes or shut off the water, but they switched off the  heating. Big freeze, plastic pipes burst or displaced and didn't come together properly. So the water tank upstairs was perpetually filling and draining. By the time the neighbours heard the alarm the inside of the house had collapsed.

The pipes are clunking less over the day but it's getting worse again. It's spewing water boiling water more frequently.

We tracked down someone who got hold of them, it's sorted now.
Something broke.