Earlier today we reported that local militiamen in the key Yemeni port city of Aden had captured two Iranian officers suspected of aiding Houthi rebels in the battle to control the city where fighters still loyal to President Hadi are determined to beat back an advance by the Houthis in the wake of a humanitarian crisis and amid reports that the Shiite militia has its sights set on the local branch of Yemen’s central bank located in the city’s Crater district.

Now, reports suggest the Houthis are battling Saudi forces near Najran, with some contending the rebels have overtaken a Saudi post which, if true, would appear to mark an escalation in the conflict as it would indicate the Houthis are willing to take the fight to the Saudis on their own turf.

#BREAKING: Asiri: clashes reported near the Saudi city of Najran — Al Arabiya English (@AlArabiya_Eng) April 11, 2015

#BREAKING Asiri: Houthi militias are amassing close to the Saudi-Yemeni border — Al Arabiya English (@AlArabiya_Eng) April 11, 2015

Reports are now coming in that three Saudis have been killed in Houthi shelling. Via Bloomberg:

Mortar attack by Houthi rebels in Yemen fired into Saudi Arabia killed 3 Saudi soldiers and injured 2 others, the state-run Saudi Press Agency reported, citing unidentified official.

Three Saudi soldiers killed in the border city of Najran by Houthi shelling http://t.co/CeONHY4LfX — MTV English News (@MTVEnglishNews) April 11, 2015

Either this represents a rather brash move by the Houthis to demonstrate that the best defense is indeed a good offense, or perhaps there's a degree to which an "offensive" maneuver by the rebels would prove very useful when it comes to justifying Saudi boots on the ground. Or maybe, as the events that transpired early Saturday suggest, the Shiite rebels are becoming more confident that their assumed benefactor may be willing to remove the "proxy" from the term "proxy war."