I am a resident of Karachi, Pakistan. I intend to invest some amount in a religiously acceptable manner. I was considering putting it in a savings account at a local bank or some government bonds etc.
if it is not allowed can you please shed light on the investment options allowed in islam

Keeping ones money in a saving system is always allowed. Banks are also a source of saving money etc. if one deposit the money with the intention of saving his earnings it is allowed. The only condition is if they dont give anything extra or give less then what was expected, one has no right to demand.