MEXICO CITY (AP) — Mexico said Thursday it has found migrants riding on about half of trains inspected.

While the largest number of migrants were detained while walking — 41,649 between June and Dec. 22 — many migrants walk along tracks hoping to hop onto a passing train.

About 2,800 migrants were found hidden in trucks and almost 3,500 were detained aboard buses.

The government presented figures on its crackdown on migrants, which started in May.

So far in 2019, Mexico has detained 178,917 migrants, mainly Central Americans, and deported 84,327.

In the first 11 months of 2019, Mexico has received 66,915 asylum claims, more than double the 29,631 it received in all of 2018.