Yemen's Houthi rebels have released what they say is new footage showing Saudi troops engaged in cross-border raids.
Riyadh, however, has denied any incursion into neighbouring Yemen.
Saudi Arabia began bombarding suspected Houthi positions earlier this month after they apparently crossed into Saudi territory and seized control of a small area.
The Houthis say that the Saudis have been allowing Yemeni troops to use the area to attack their positions.
The Shia Muslim Houthi fighters have been battling the government of Ali Abdullah Saleh, the Yemeni president, since 2004, citing political, economic and religious marginalisation.
Saudi officials claim that the fighting in northern Yemen is being supported by Iran and could be helping al-Qaeda fighters to cross to their side of the border.
Al Jazeera's Nicole Johnston reports.
Source: Al Jazeera and agencies