Fuel guage & warning light on sportrak


Just bought an old sportrak (1992 1.6i just 41k on clock)

Everything was working fine on way home - after parking up my girlfriend came out to take a look and we found that the fuel guage had dropped to empty and a warning light had come on the dash (an 'i' in a circle)

I put in £10 fuel for the 6 mile journey home so it shouldn't be empty

Any ideas what this could mean? I don't have any manuals etc.