European benchmarks sank Thursday as a cocktail or irritants conspired to agitate investors.

Commodities weighed heavily after futures prices fell overnight in China for the fourth session running.

Price action in materials markets came closely on the heels of the much vaunted tax reform plan that was released by the White House late Wednesday.

The plan was criticized for a lack of detail by some and for coming across as a huge tax cut for the rich by others. Either way, it left markets underwhelmed.

Corporate earnings were also mixed, throwing a handful of small gainers and a number of large fallers into the mix during the session.

A mixed message from the European Central Bank did little to move the dial across equity markets during noon trading, after Mario Draghi & Co heralded a strengthening recovery in the euro area but remained on hold as far as policy goes.

The FTSE 100 closed 0.71% lower at 7,237 in London while the DAX dropped 0.23% in Frankfurt to settle at 12,443. In Paris the CAC 40 slipped 0.30% to close at 5,271.

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In individual stocks, mining companies BHP Billiton (BHP) - Get BHP Group Ltd Sponsored ADR Report, Fresnillo (FNLPF) , Glencore (GLNCF) and Antofagasta (ANFGY) all saw big losses in London during the session, each falling 3% or more.

In Paris, oil and gas engineer Technip (TKPPY) reported a poorer than expected set of numbers for the first-quarter and was also a victim of sour sentiment toward the resources sector on the day, both of which helped push the shares more than 6% lower on the CAC.

In Frankfurt Lufthansa (DLAKY) stock hit turbulence Thursday morning, falling more than 5% close to the bottom of the DAX, after a cautious tone from management led investors to overlook what was otherwise a solid set of first-quarter numbers.

Deutsche Bank (DB) - Get Deutsche Bank AG Report was also a big faller following its first quarter numbers. The lender beat estimates for earnings but investors were unsettled by a poor performance from its trading division, which has lagged the rest of the industry.

In Spain, Banco Popular (BPESF) stock plummeted more than 6% after first-quarter results from a key competitor brought investors' attention to bear on net interest income in the Spanish market, which is an achilles heel for the lender.

The rout came after first-quarter results from rival BBVA (BBVA) - Get Banco Bilbao Vizcaya Argentaria, S.A. Sponsored ADR Report showed Spanish net interest income, on which Popular is highly dependent, under continued pressure as years of record low interest rates bite deeper into the underbelly of banking sector profitability.

International diversification, substantial trading businesses and fixed-fee income pools has helped both BBVA and its larger rival, Banco Santander (SAN) - Get Banco Santander S.A. Sponsored ADR Report , to still post strong numbers at the group level in recent days.

However, Banco Popular has very little international diversification and is more reliant on net interest income in its home market than many of its peers.