to enter or entering after "see"

[Deepurple]

May I ask which of the following ones is correct?

It has been proved that he was seen to enter the building.
It has been proved that he was seen entering the building.

Thanks for helping.

[bhaisahab]

Both are correct.

[Deepurple]

Both are correct.

Tell me more, tell me more...
the reasons?

[bhaisahab]

'To be seen to do something' is correct it means the same as 'To be seen doing something' it works only in the passive voice, you can't say 'I saw him to do something' for example, but you can say 'I saw him doing something.'

[Clark]

Hi Bhaisahab,
Is it possible that the partciple focuses on the moment the person was entering the building while the infinitive lays stress on the fact that he did come in?

[bhaisahab]

Yes, you are right Clark.