Most humane way to kill flies?

[SamMil]

Can anyone recommend the most effective and quickest way to kill house flies? I've been putting up with them for a couple of weeks as I thought they'd die off on their own gradually but they haven't!

I think we need to kill them unfortunately, but I'd prefer something that kills them quickly - I hate the fly paper where they just stick & take ages to die

Any suggestions?

You can also fill a small container with vinegar and water, with a drop of washing up liquid mixed in. It worked for me, but your house will stink of vinegar.

Thanks for the advice everyone We bought an electric fly swatter and it worked perfectly - killed them immediately too, so although I still feel bad, at least they died quickly! We do have 2 cats but they obviously aren't doing their job!

Our house is a new build and only been finished for a few months - no house plants, bin emptied regularly etc, but we do live in the countryside and have horses in the field outside, so lots of flies if you leave the windows/doors open!