Police working through Mischief Night returned to their car to find a note from a neighbour stuck to their window.
Officers from Lancashire Police, working in Ormskirk, were in the area on Saturday night to help people feel safe over Halloween weekend.
While speaking to people who live in the town a small note was left on the car by someone thanking them for their presence.
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The message was written on a piece of paper and said: "I live at number *blank* and I can't tell you how grateful I am for your presence."
Posting a picture of the note to Facebook, officers also outlined what they had been doing through the night,
A spokesperson said: "A couple of our Special Constabulary colleagues saying hello to our mounted officers and a lovely note of thanks from one of our residents.
"Thankfully the majority of people are enjoying the Halloween weekend responsibly."
According to the post, officers only had to deal with one incident of antisocial behaviour.
They added: "We have just had to speak to a small group in Ormskirk town centre about their behaviour but they are now on their way home as I think it was past their bed time."
Earlier in the night, officers posted advice to parents for the night.
They said: "Do you know where your child is tonight?
"We’d like to appeal to parents – do you know where your children are?
"With the message to stay safe and enjoy Halloween responsibly.
"The consequences of antisocial behaviour and criminality can have a lasting impact on a young person’s life and on those affected by their actions."
