What happens when an investigator returns from Another World to a location containing monsters?

I know that an investigator does not have to fight or evade monsters on the turn he/she returns to Arkham. But what happens to the monsters in a location if the investigator manages to close and seal the location during the same turn?

In a game last night Mandy Thompson returned from Another World to a location with 2 Warlocks (Yellow border). As per the rules she didn't have to fight or evade them during that turn. In the next Arkham encounters phase she successfully closed the gate and paid 5 clue tokens to seal it. But I wasn't sure what effect, if any, this would have on the Warlocks.

In the actual game I reasoned that the Elder sign would banish the monsters from the location and simply returned them to the cup. Was that correct play?

Should the monsters have merely been moved to the adjacent street area? Or should the monsters have stayed put regardless of the Elder sign token.

Welcome to the Carnival, Lee418!

If the Investigator returns to Arkham following their 2nd Other World Encounter, he may choose to ignore any and all monsters on the Gate. The Investigator may choose to combat one or more monsters while ignoring others. This ONLY happens if the Investigator has, during Movement, returned to Arkham . If, however, you have an Other World encounter which allows you to Return to Arkham during the Other World Phase, you DO NOT have the benefit of ignoring the monster(s) on the Gate during the following turn's Movement Phase .

As Warlocks have the 'circle' dimensional symbol, if the Gate Mandy closed had the same symbol, you would return them to the cup. However, in the case of Warlocks , if you have the right weapon, it's best to defeat them as they would be returned to the box, not the cup, and Mandy would yield 4 Clue tokens (2 each).

E lder Signs do not banish monsters simply residing at the Gate nor does it move them to an adjacent street area.

E lder Signs do not banish monsters simply residing at the Gate nor does it move them to an adjacent street area.

I got a little confused because I remembered reading about Elder Signs preventing monsters from appearing at sealed locations (AH rulebook p.18), but I wasn't sure whether this applied to monsters who were already at a location prior to it being sealed.

Now I know. Thank you.

The monster at the gate location returning to the cup is actually a house rule reccommended by the creator of the game;

"Rule 6 - Monster Guards Sucked Through Closing Gates

E lder Signs do not banish monsters simply residing at the Gate nor does it move them to an adjacent street area.

I got a little confused because I remembered reading about Elder Signs preventing monsters from appearing at sealed locations (AH rulebook p.18), but I wasn't sure whether this applied to monsters who were already at a location prior to it being sealed.

Now I know. Thank you.

Yes. A sealed location is no longer considered an unstable location, but becomes stable, so neither monsters nor gates can appear there, but monsters already "on the spot" are not removed unless their dimensional symbol matches the symbol on the gate you close / seal. So, as Joe said, in case you're closing / sealing the gate and you can't remove the monsters, you'll have to deal with them during the Movement Phase of the following turn