3 bird like crafts seen at night

My boyfriend and I were on the roof terrace whilst on holiday in playa del Carmen, Mexico.  It was night time, and I suddenly pointed out 3 bird like objects in the sky that were in sync vertically straight ahead.  They were lit up in the sky and were alot bigger than the stars and aircraft we were spotting in the sky that night.   We watched them move from right to left and disappear.  2 of the objects stayed together as they went out of sight and the other went to the slightly to the left.
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Hello Peter.
They looked like massive birds in the sky but could tell they were some distance away and you would not see a bird that big from that distance, it was dark but they were shining white in the sky, and you could see the 3 of them flying vertically together just above 3 story buildings.  The moon was big at the time before it rose in they.  They were about 20x bigger than the stars in the sky and about an 8th smaller than the moon.
I hope that helps, if you need anymore info, please let me know.  It's the first time me and my boyfriend have ever seen anything that we were unable to identify in the sky.
Kind regards,
((name deleted))
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