A private person making an arrest must inform the person to be arrested of the intention to arrest the person, and of the cause of the arrest, unless:
1. The person to be arrested then is engaged in the commission of an offense;
2. Such person is pursued immediately after its commission or after an escape;
3. Such person flees or forcibly resists before the person making the arrest has opportunity to inform the person; or 4. The giving of such information will imperil the arrest.