From Sahih Bukhari (Hadith 7384):
Narrated Anas:The Prophet (ﷺ) said, "(The people will be thrown into Hell ( Fire) and it will keep on saying, 'Is there any more?' till the Lord of the worlds puts His Foot over it, whereupon its different sides will come close to each other, and it will say, 'Qad! Qad! (enough! enough!) By Your 'Izzat (Honor and Power) and YOUR KARAM (Generosity)!' Paradise will remain spacious enough to accommodate more people until Allah will create some more people and let them dwell in the superfluous space of Paradise
Reference: Bukhari 7384