  Electric current and spacial displacement due to trembling motion
[Zitterbewegung (ZB)] of electrons in graphene in the presence of an external
magnetic field are described. Contributions of both inequivalent $K$ points in
the Brillouin zone of graphene are considered. It is shown that, when the
electrons are prepared in the form of wave packets, the presence of a
quantizing magnetic field $B$ has very important effects on ZB. (1) For $B\neq
0$ the ZB oscillations are permanent, for B=0 they are transient. (2) For
$B\neq 0$ many ZB frequencies appear, for B=0 only one frequency is at work.
(3) For $B\neq 0$ both interband and intraband (cyclotron) frequencies
contribute to ZB, for B=0 there are no intraband frequencies. (4) Magnetic
field intensity changes not only the ZB frequencies but the entire character of
ZB spectrum. An emission of electromagnetic dipole radiation by the trembling
electrons is proposed and described. It is argued that graphene in a magnetic
field is a promising system for an experimental observation of Zitterbewegung.
