Yell/shout to do

1.He went down the tunnel, where a security guard saw him and yelled to stop.

2.A German soldier shouted to leave the old people inside and to the side of the car.

I have two questions about both sentences.

I found them in some English books.

Q1) Are "yelled to stop" and "shouted to leave" correct English?

Q2) What do "Yelled to stop" and "shouted to leave" mean?

I think both mean like "yelled at someone to stop" and "shouted at someone to stop".

Thanks a lot.