It was narrated that Anas said:
"I went out with the Messenger of Allah (ﷺ) from Al-Madinah to Mekkah, and he continued to shorten his prayers, and he stayed there for ten days." (DE)
Reference (DE): Sunan an-Nasa'i 1438 (DE)
In-book reference (DE): Book 15, Hadith 6 (DE)
English translation (DE): Vol. 2, Book 15, Hadith 1439 (DE)