B767-300 flight crew reported a cargo fire warning and returning to departure airport.

Narrative:

After crossing the northern shore of country X we got a main cargo deck fire warning. The checklist was started and the decision to return to ZZZ was made. Crew coordination and checklist usage went really well. I computed the non normal landing distances and it was decided to land runway xx as it was the most expeditious. On final we received a left engine fire indication for one second; and then the indication extinguished. We landed without issue and rolled to the end of the runway to clear. ATC and crash fire rescue said no indication of fire. It was decided to taxi into the gate. On taxi in we got multiple left engine fire warnings. After block in 4 tire fuse plugs blew.all facets worked well together; inside and outside the cockpit. Some issues we faced; the EICAS message for main cargo deck fire/smoke did not match the QRH message. We never train main cargo deck fire in the sim because the sim doesn't have that panel. The lithium batteries on board were scattered throughout the cargo compartment; and would not have been accessible if we needed to. Although I'm not sure we could've done anything even if we could've gotten to their location. Crew scheduling assigned us to another flight after we returned; we were legal for it; but no one bothered to ask if we were okay; and if we felt safe to do another flight. We are humans; that was scary; have some empathy.

Original NASA ASRS Text

Title: B767-300 flight crew reported a cargo fire warning and returning to departure airport.

Narrative: After crossing the northern shore of Country X we got a main cargo deck fire warning. The checklist was started and the decision to return to ZZZ was made. Crew coordination and checklist usage went really well. I computed the non normal landing distances and it was decided to land Runway XX as it was the most expeditious. On final we received a left engine fire indication for one second; and then the indication extinguished. We landed without issue and rolled to the end of the runway to clear. ATC and crash fire rescue said no indication of fire. It was decided to taxi into the gate. On taxi in we got multiple left engine fire warnings. After block in 4 tire fuse plugs blew.All facets worked well together; inside and outside the cockpit. Some issues we faced; the EICAS message for main cargo deck fire/smoke did not match the QRH message. We never train main cargo deck fire in the sim because the sim doesn't have that panel. The lithium batteries on board were scattered throughout the cargo compartment; and would not have been accessible if we needed to. Although I'm not sure we could've done anything even if we could've gotten to their location. Crew scheduling assigned us to another flight after we returned; we were legal for it; but no one bothered to ask if we were okay; and if we felt safe to do another flight. We are humans; that was scary; have some empathy.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1744768
Time
Date	202006
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZZ.ARTCC
State Reference	FO
Aircraft 1
Make Model Name	B767-300 and 300 ER
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Cargo Compartment Fire/Overheat Warning
Person 1
Function	Pilot Not Flying
Qualification	Flight Crew Instrument Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Pilot Not Flying
Qualification	Flight Crew Instrument Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor