‘Sec. 1752. Restricted building or grounds
‘(a) Whoever--
‘(1) knowingly enters or remains in any restricted building or grounds without lawful authority to do so;
‘(2) knowingly, and with intent to impede or disrupt the orderly conduct of Government business or official functions, engages in disorderly or disruptive conduct in, or within such proximity to, any restricted building or grounds when, or so that, such conduct, in fact, impedes or disrupts the orderly conduct of Government business or official functions;
‘(3) knowingly, and with the intent to impede or disrupt the orderly conduct of Government business or official functions, obstructs or impedes ingress or egress to or from any restricted building or grounds; or
‘(4) knowingly engages in any act of physical violence against any person or property in any restricted building or grounds;
or attempts or conspires to do so, shall be punished as provided in subsection (b).