Militares pro Maduro atacaron a @jguaido y @leopoldolopez y a los militares sublevados en el doatribuidor Altamira pic.twitter.com/xJynGSJU3L

— Rafael Hernández (@sincepto) April 30, 2019

update 2: Secretary of State Mike Pompeo says Guaidó has the White House's full support in the opposition leader's call for military uprising against Maduro, and is monitoring closely.

There are further unconfirmed reports suggesting limited groups of National Guard soldiers may be defecting to the Guaido-led opposition, and at least some videos coming out of Caracas appear to show clashes between the rival factions, but Maduro is claiming to have the "total loyalty" of the armed forces.