Anwar al-Awlaki & Samir Khan

[classicman]

I was going off of section (5)

A person wishing to renounce his or her U.S. citizenship must voluntarily and with intent to relinquish U.S. citizenship:

appear in person before a U.S. consular or diplomatic officer,
in a foreign country (normally at a U.S. Embassy or Consulate); and
sign an oath of renunciation

Renunciations that do not meet the conditions described above have no legal effect. Because of the provisions of section 349(a)(5), Americans cannot effectively renounce their citizenship by mail, through an agent, or while in the United States. In fact, U.S. courts have held certain attempts to renounce U.S. citizenship to be ineffective on a variety of grounds, as discussed below.

from here