Bees do not sting tomatos.

You are right. It could be fruit fly that looks like bees. Besides tomatoes, it stung my starfruit in all stages as well. I normally wrapped my starfruits with wrapper.

These flies laid eggs in the fruits and soon the maggots will eat the fruits. Bad, bad bad. So far, my first turning yellowish 4 tomatoes were either spoiled or cracked (There are lots of rains this last two weeks and still raining). The rest of smaller ones are almost all being stung and also blossom drop. I am sad :(. What a disappointing end with no fruits after happily seeing it flowered and beared fruits.

This could be the Tomato Fruitworm, aka the Corn Earworm, but the adult is a moth. With bees and wasps only the queen, attended by workers in the hive, lay eggs. There is no bee, or wasp, I am aware of that would lay eggs in any fruit. For control of the Tomato Fruitworm sprays of Bacillus Thuringiensis - Kurstaki are effective, if sprayed early enough, but nothing will help once the larva are inside the tomato.

sounds like you have fruit fly, where we live we get the tropical fruit fly so we put into play mangement practises to get some control, so you will have to research what your fly is and then find the best management practise, we have found non-chemical application methods to use in our case.

len

Here is a link that might be useful: len's garden page